Engineering and Administrative Recommendations for
Water Fluoridation, 1995
Summary
In April and September 1993, CDC convened two advisory
workshops to
review and revise fluoridation recommendations. Since 1979, CDC has
developed guidelines and/or recommendations for managers of
fluoridated
public water systems. This report summarizes the results of these
two
workshops and consolidates and updates CDC's previous
recommendations.
Implementation of these recommendations should contribute to the
achievement of continuous levels of optimally fluoridated drinking
water
for the U.S. population, minimize potential fluoride overfeeds
(i.e., any
fluoride level that is greater than the recommended control range
of the
water system), and contribute to the safe operation of all
fluoridated
water systems. The report delineates specific recommendations
related to
the engineering aspects of water fluoridation, including
administration,
monitoring and surveillance, technical requirements, and safety
procedures.
The recommendations address water fluoridation for both community
public
water supply systems and school public water supply systems.
INTRODUCTION
Water fluoridation is the deliberate addition of the natural trace
element
fluorine (in the ionic form as fluoride) into drinking water in
accordance
with scientific and dental guidelines (1-9). Fluoride is present in
small
yet varying amounts in almost all soil, water supplies, plants, and
animals
and, thus, is a normal constituent of all diets (10). In mammals,
the
highest concentrations are found in the bones and teeth.
Since 1945, many studies have demonstrated the oral health benefits
of
fluorides and fluoridation. In 1945 and 1947, data from four
studies (Grand
Rapids, Michigan; Newburgh, New York; Brantford, Ontario CanadaĄ;
and
Evanston, Illinois) demonstrated the oral health benefits of
fluoridated
water in several communities and established water fluoridation as
a
practical, effective public health measure that would prevent
dental caries
(11-14). Data have consistently indicated that fluoridation is safe
and is
the most cost-effective and practical means for reducing the
incidence of
dental caries (tooth decay) in a community (15-28). However,
additional
studies have demonstrated that the oral health benefits are reduced
if the
optimal level of fluoride is not maintained (29-30). In the past,
maintaining the optimal level without active
monitoring/surveillance
programs has been difficult. In the 1970s, approximately half of
the
systems presumed to be fluoridated were not consistently
maintaining the
optimal fluoride concentrations.
Since the late 1970s, CDC has developed technical and
administrative
guidelines and/or recommendations for correcting inconsistencies in
fluoridated public water supply systems (CDC, unpublished data;
31-33). In
April and September of 1993, CDC convened two advisory workshops to
review
and revise fluoridation guidelines. Participants included 11
technical
experts from state agencies and the Indian Health Service.
Additional
comments were obtained from state dental officials, state drinking
water
personnel, and others (e.g., schools of public health, dental
societies,
and engineers from private industry). The intent of these
recommendations
is to provide guidance to federal, state, and local officials
involved in
the engineering or administrative aspects of water fluoridation,
which
should help ensure that fluoridated water systems are providing
optimal
fluoride levels.
This report provides information from earlier studies linking
fluoridation
with the reduction of dental caries, summarizes the conclusions of
the
workshops, provides recommendations for fluoridation of both
community and
school public water supplies, and consolidates previous
recommendations.
These recommendations are written with the assumption that the
reader
either has an engineering background or at least is familiar with
basic
water supply engineering principles. As an aid to readers, a
glossary of
technical terms is included.
BACKGROUND
History of Water Fluoridation
The capacity of waterborne fluoride to prevent tooth decay was
recognized
in the early 1900s in Colorado Springs, Colorado, when a dentist
noted that
many of his patients' teeth exhibited tooth discoloration (i.e.,
"Colorado
Brown Stain"). Because that condition had not been described
previously in
the scientific literature, he initiated research about the
condition and
found that Colorado Brown Stain -- now termed fluorosis (mottled
enamel) --
was prevalent throughout the surrounding El Paso County. The
dentist
described fluorosis and made recommendations on how to prevent its
occurrence (34,35). Other dentists and researchers also had noted
the
occurrence of fluorosis and theorized that fluoride in the water
might be
associated with the condition. They also noted that persons who had
fluorosis had almost no dental caries (36). The dentist in Colorado
subsequently collaborated with the U.S. Public Health Service to
determine
if fluoride could be added to the drinking water to prevent
cavities
(2,37). Further studies were conducted that confirmed the
cause-and-effect
relation between fluoridation and the reduction of dental caries
(1,3,6,38,39).
National, State, and Local Fluoride Guidelines
A public water system can be owned by the municipality that it
serves, or
it may be corporately owned. A public water system is not defined
by its
ownership. To be considered a public water system, the system must
have
greater than or equal to 15 service connections or must regularly
serve an
average of greater than or equal to 25 persons for greater than or
equal to
60 days per year. Public water systems do not necessarily follow
city,
county, or even state boundaries. For example, a large municipality
may be
served by one water system or by multiple water systems; a public
water
system may serve several municipalities. Individual states'
regulations
and/or guidelines for respective water systems range from specific
to
general. The recommendations and guidelines for water fluoridation
must be
sufficiently general to allow for individual states' variations in
nomenclature and organization.
Schools that have individual water systems, which are considered
public
water systems, are subject to all the rules that apply to public
water
systems. However, because of limits on use and the size of these
systems,
they have been included in a subcategory of public water systems
referred
to as nontransient, noncommunity public water systems. Special
recommendations and guidelines that apply to school public water
systems
are included in this report.
Although no national regulations or laws govern water fluoridation,
many
federal agencies concur that water fluoridation is beneficial to
public
health (M. Cook, personal communication; 40). The Environmental
Protection
Agency (EPA), through the Safe Drinking Water Act of 1986, has
established
national requirements for public water systems but not for adjusted
water
fluoridation. EPA also has established a maximum concentration
level for
natural fluoride in drinking water. If the fluoride content in
drinking
water exceeds this level, it must be removed. *
RECOMMENDATIONS FOR FLUORIDATED COMMUNITY PUBLIC WATER SUPPLY
SYSTEMS
Administration
Personnel
Each state should designate a state fluoridation
administrator who
will be responsible for a) managing the fluoridation
program, b)
promoting water fluoridation, and c) providing liaison
with other
state and federal agencies. This person should be selected
from
either the dental program or the drinking water program.
Each state should employ at least one full-time state
fluoridation
specialist, whose primary responsibilities will be to a)
provide
for site visits, b) provide for start-up visits, c) assist
in the
training of water plant operators, d) provide surveillance
for all
fluoridated water systems, and e) resolve problems. In
larger
states (e.g., Montana), this specialist should be
responsible for
no more than 75 fluoridated water systems and in smaller
states
(e.g., Massachusetts), for no more than 100.
The staff of both the state dental and state drinking
water
programs should maintain communication regarding all
aspects of
water fluoridation in the state.
A trained water plant operator (one who has received
greater than
or equal to 6 hours of fluoridation training) should be
responsible for each fluoridated water system.
System Reporting Requirements
Whenever the fluoride content of drinking water is adjusted,
a person
should be designated to report daily fluoride test results to
the
appropriate state agency. These reports should be submitted
each
month.
State Reporting Requirements
Each month, the state agency should report back to the
respective
operators the test results of monthly split or check
samples taken
from each fluoridated water system.
Each state should compile and maintain the following
information
on fluoridation:
Names of all fluoridated water systems in the state;
Names of all consecutive systems (i.e., a public water
system
that buys water from another public water system) that
purchase
water from fluoridated water systems; and
Names of all communities served by each fluoridated
water
system and each consecutive water system.
Each state should supply CDC (National Center for Chronic
Disease
Prevention and Health Promotion, Division of Oral Health)
with the
preceding information at least yearly (41).
Each state should participate in the Association of State
and
Territorial Dental Directors (ASTDD) quarterly reporting
system.
Quarterly submission of data will assist states by
providing
national data against which to compare their quality and
by
providing a standard procedure for conducting quality
assessments
of their fluoridation systems. (See Exhibit A for ASTDD
instructions.)
Each state should develop a system to notify health-care
providers
(i.e., dentists, pharmacists, and physicians) when a new
fluoridation system is initiated and when one is
discontinued.
Training
All state fluoridation specialists should attend CDC's
basic
fluoridation training course or a similar course at least
once and
CDC's advanced workshop or a similar workshop once every 3
years.
State personnel must provide training for all water plant
operators for each new fluoridated water system before
that system
is started. This start-up training must address the
following:
Information specific to the water plant and equipment,
including how to test water for fluoride, under the
supervision
of state personnel;
Reporting requirements to the state; and
Information on public health benefits of fluoride and
the role
of water plant personnel in providing those benefits.
Each state should integrate a minimum of 1 hour of
precertification training in water fluoridation into the
basic
certification training course for water plant operators.
This
precertification training should include the following:
Public health benefits of fluoridation and the
operator's key
role in preventing dental caries;
The importance of maintaining the optimal fluoride
level; and
Technical requirements regarding the types of systems
and the
testing procedures.
Each state should provide an annual fluoridation training
course
for operators. This training should be a minimum of 6-8
hours and
should address all aspects of water fluoridation,
including
fluoride analyses. The course may offer credit toward
continuing
education requirements for operator certification. In
states where
the operator turnover rate is low, training may be
provided every
other year.
Inspection
State personnel must provide a detailed, on-site
inspection of
each new fluoridation system before the system start-up to
ensure
that construction and installation are in accordance with
state-approved plans and specifications. (See Exhibit B
for
fluoridation facility fact sheet to be completed for each
facility
inspected.)
State personnel should inspect individual water
fluoridation
systems at least once a year. (See Exhibit C for sample
inspection
form.) This comprehensive inspection should include, at a
minimum,
the following:
An evaluation of the fluoride testing equipment;
An inspection of the chemical (fluoride) storage area;
An inspection of the operation and maintenance manuals;
A check to ensure that only state-approved backflow
preventers
and antisiphon devices (as well as testing procedures
for such
equipment) are being used;
An evaluation of the on-site emergency plans
(stipulated
actions in case of overfeed and public-notification
procedures
to be followed) (Table_1);
An inspection of the plant's security (e.g., placement
of
appropriate signs and fences and preventing entrance by
unauthorized persons); and
An inspection of the on-site safety equipment available
to the
operator.
Actions in Case of Overfeed
State personnel must provide each water plant with procedures
to
follow in the event of an overfeed. These operating
procedures should
address the following:
Shutting down the equipment;
Notifying appropriate state personnel;
Flushing out the water lines containing the high (greater
than or
equal to 10 mg/L) fluoride concentration; and
Notifying the public to prevent consumption of drinking
water with
high fluoride concentration.
Monitoring and Surveillance
Water system personnel must monitor daily fluoride levels in
the
water distribution system. Samples that will reflect the
actual level
of fluoride in the water system should be taken at points
throughout
the water system. The sites where samples are taken should be
rotated
daily.
At least once each month, water system personnel should
divide one
sample and have one portion analyzed for fluoride by water
system
personnel and the other portion analyzed by either the state
laboratory or a state-approved laboratory.
Each water system must send operational reports to the state
at least
monthly. The report must include:
The amount and type of chemicals fed and the total number
of
gallons of water treated per day;
The results of daily monitoring for fluoride in the water
distribution system; and
The results of monthly split sample(s).
The calculated dosage should be cross-checked against the
reported
fluoride levels to spot chronic nonoptimal operation.
The system's raw water source (i.e., water that has not been
treated)
should be analyzed annually for fluoride by either the state
laboratory or a state-approved laboratory, or in accordance
with
state regulations.
If the optimal fluoride level in a community public water
supply
system has not been set by the state, optimal fluoride levels
should
be established (Table_2). (State regulations supersede
recommended optimal fluoride levels contained in this
report.)
All state laboratories should participate in CDC's Fluoride
Proficiency Testing Program to ensure the accuracy of their
fluoride
testing program.
Technical Requirements
General
The fluoride feed system must be installed so that it
cannot
operate unless water is being produced (interlocked). For
example,
the metering pump must be wired electrically in series
with the
main well pump or the service pump. If a gravity flow
situation
exits, a flow switch or pressure device should be
installed. The
interlock might not be required for water systems that
have an
operator present 24 hours a day.
When the fluoridation system is connected electrically to
the well
pump, it must be made physically impossible to plug the
fluoride
metering pump into any continuously active ("hot")
electrical
outlet. The pump should be plugged only into the circuit
containing the interlock protection. One method of
ensuring
interlock protection is to install on the metering pump a
special,
clearly labeled plug that is compatible only with a
special outlet
on the appropriate electrical circuit. Another method of
providing
interlock protection is to wire the metering pump directly
into
the electrical circuit that is tied electrically to the
well pump
or service pump, so that such hard wiring can only be
changed by
deliberate action.
A secondary flow-based control device (e.g., a flow switch
or a
pressure switch) should be provided as back-up protection
in water
systems that serve populations of less than 500 persons.
The fluoride injection point should be located where all
the water
to be treated passes; however, fluoride should not be
injected at
sites where substantial losses of fluoride can occur
(e.g., the
rapid-mix chemical basin). In a surface-water treatment
plant, the
ideal location for injecting fluoride is the rapid sand
filter
effluent line going into the clearwell.
The fluoride injection point in a water line should be
located in
the lower one third of the pipe, and the end of the
injection line
should extend into the pipe approximately one third of the
pipe's
diameter (31,32).
A corporation stop valve should be used in the line at the
fluoride injection point when injecting fluoride under
pressure. A
safety chain must always be installed in the assembly at
the
fluoride injection point to protect the water plant
operator if a
corporation stop valve assembly is used.
Two diaphragm-type, antisiphon devices must be installed
in the
fluoride feed line when a metering pump is used. The
antisiphon
device should have a diaphragm that is spring-loaded in
the closed
position. These devices should be located at the fluoride
injection point and at the metering pump head on the
discharge
side. The antisiphon device on the head of the metering
pump
should be selected so that it will provide the necessary
back
pressure required by the manufacturer of the metering
pump.
All antisiphon devices must be dismantled and visually
inspected
at least once a year. Schedules of repairs or replacements
should
be based on the manufacturer's recommendations. Vacuum
testing for
all antisiphon devices should be done semiannually.
Operation of a
fluoridation system without a functional antisiphon device
can
lead to an overfeed that exceeds 4 mg/L.
The fluoride metering pump should be located on a shelf
not more
than 4 feet (1.2 m) higher than the lowest normal level of
liquid
in the carboy, day tank, or solution container. A flooded
suction
line is not recommended in water fluoridation.
For greatest accuracy, metering pumps should be sized to
feed
fluoride near the midpoint of their range. Pumps should
always
operate between 30%-70% of capacity. Metering pumps that
do not
meet design specifications should not be installed.
Oversized
metering pumps should not be used because serious
overfeeds (i.e.,
an overfeed that exceeds 4 mg/L) can occur if they are set
too
high. Conversely, undersized metering pumps can cause
erratic
fluoride levels.
The priming switch on the metering pump should be
spring-loaded to
prevent the pump from being started erroneously with the
switch in
the priming position.
An in-line mixer or a small mixing tank should be
installed in the
finished water line exiting from the water plant if the
first
customer is less than or equal to 100 feet (less than or
equal to
30.5 m) from the fluoride injection point and if there is
no
storage tank located in the line before the water reaches
the
customer. The minimum distance is 100 feet, assuming there
are
typical valves and bends in the water line that allow for
adequate
mixing.
Flow meter-paced systems should not be installed unless
the rate
of water flow past the point of fluoride injection varies
by more
than 20%.
A master meter on the main water service line must be
provided so
that calculations can be made to confirm that the proper
amounts
of fluoride solution are being fed.
The fluoride feed line(s) should be either color coded,
when
practical, or clearly identified by some other means.
Color coding
helps prevent possible errors when taking samples or
performing
maintenance. The pipes for all fluoride feed lines should
be
painted light blue with red bands. The word "fluoride" and
the
direction of the flow should be printed on the pipe (42).
Fluoride feed equipment, controls, safety equipment,
accessory
equipment, and other appurtenances must be inspected
annually.
All hose connections within reach of the fluoride feed
equipment
should be provided with a hose bibb vacuum breaker.
All fluoride chemicals must conform to the appropriate
American
Water Works Association (AWWA) standards (B-701, B-702,
and B-703)
to ensure that the drinking water will be safe and potable
(43-45).
Storage should be provided for at least a 3-month supply
of
fluoride chemical to minimize the effect of a possible
fluoride
chemical shortage. Shortages have occurred sporadically in
the
past (CDC, unpublished report, 1986; 46).
Cross-connection controls that conform to state
regulations must
be provided.
Sodium Fluoride Saturator Systems
The minimum depth of sodium fluoride in a saturator should
be 12
inches (30.5 cm). This depth should be marked on the
outside of
the saturator tank. The saturator should never be filled
so high
that the undissolved chemical is drawn into the pump
suction line.
Only granular sodium fluoride should be used in
saturators,
because both powdered and very fine sodium fluoride tend
to cause
plugging in the saturator.
The water used for sodium fluoride saturators should be
softened
whenever the hardness exceeds 50 parts per million (ppm).
Only the
water used for solution preparation (i.e., the make-up
water)
needs to be softened.
A flow restrictor with a maximum flow of 2 gallons (7.6 L)
per
minute should be installed on all upflow saturators.
In the event of a plant shutdown, the make-up water
solenoid valve
should be physically disconnected from the electrical
service.
For systems that use less than or equal to 10 gallons
(less than
or equal to 38 L) of saturator solution per day, operators
should
consider using an upflow saturator that is manually filled
with
water.
In an upflow saturator, either an atmospheric vacuum
breaker must
be installed or a backflow prevention device must be
provided in
accordance with state or local requirements. The vacuum
breaker
must be installed according to the manufacturer's
recommendations.
A sediment filter (20 mesh) should be installed in the
water
make-up line going to the sodium fluoride saturators. The
filter
should be placed between the softener and the water meter.
A water meter must be provided on the make-up water line
for the
saturator so that calculations can be made to confirm that
the
proper amounts of fluoride solution are being fed. This
meter and
the master meter should be read daily and the results
recorded.
Unsaturated (batch-mixed) sodium fluoride solution should
not be
used in water fluoridation.
Fluorosilicic Acid Systems
To reduce the hazard to the water plant operator,
fluorosilicic
acid (hydrofluosilicic acid) must not be diluted. Small
metering
pumps are available that will permit the use of
fluorosilicic acid
for water plants of any size.
No more than a 7-day supply of fluorosilicic acid should
be
connected at any time to the suction side of the chemical
feed
pump. All bulk storage tanks with more than a 7-day supply
must
have a day tank. A day tank should only contain a small
amount of
acid, usually a 1- or 2-day supply.
Day tanks or direct acid-feed carboys/drums should be
located on
scales; daily weights should be measured and recorded.
Volumetric
measurements, such as marking the side of the day tank,
are not
adequate for monitoring acid feed systems.
Carboys, day tanks, or inside bulk storage tanks
containing
fluorosilicic acid must be completely sealed and vented to
the
outside.
Fluorosilicic acid should be stored in bulk, if
economically
feasible.
Bulk storage tanks must be provided with secondary
containment
(i.e., berms) in accordance with state/local codes or
ordinances.
Dry Fluoride Feed Systems
A solution tank that has a dry feeder (both volumetric and
gravimetric) must be provided.
Solution tanks should be sized according to CDC guidelines
(31).
A mechanical mixer should be used in every solution tank
of a dry
feeder when sodium fluorosilicate (i.e., silicofluoride)
is used.
Scales must be provided for weighing the amount of
chemicals used
in the dry feeder.
Testing Equipment
Operators of surface water plants should use the ion
electrode
method of fluoride analysis because chemicals (e.g., alum)
used in
a surface water plant will cause fluctuating interferences
in the
colorimetric method (SPADNS) of fluoride analysis (47).
A magnetic stirrer should be used in conjunction with the
ion
electrode method of fluoride analysis.
The colorimetric method (SPADNS) of fluoride analysis can
be used
where no interference occurs or where the interferences
are
consistent (e.g., from iron, chloride, phosphate, sulfate,
or
color). The final fluoride test result can be adjusted for
these
interferences. State laboratory personnel, the state
fluoridation
specialist, and the water plant operator should reconcile
the
interferences and make the appropriate adjustment.
Distillation is not needed when the colorimetric method
(SPADNS)
of fluoride analysis is used for testing daily fluoride
levels.
Safety Procedures
Fluoride remains a safe compound when maintained at the optimal
level in
water supplied to the distribution system; however, an operator
might be
exposed to excessive levels if proper procedures are not
followed or if
equipment malfunctions. Thus, the use of personal protective
equipment
(PPE) is required when fluoride compounds are handled or when
maintenance on fluoridation equipment is performed. The employer
should
develop a written program regarding the use of PPE. The water
supply
industry has a high incidence of unintentional injuries compared
with
other industries in the United States; therefore, safety
procedures
should be followed (48).
Operator Safety
Fluorosilicic acid
The operator should wear the following PPE:
Gauntlet neoprene gloves with cuffs, which should be
a
minimum length of 12 inches (30.5 cm);
Full face shield and splash-proof safety goggles;
and
Heavy-duty, acid-proof neoprene apron or acid-proof
clothing
and shoes.
A safety shower and an eye wash station must be
available and
easily accessible.
Sodium fluoride or sodium fluorosilicate
The operator should wear the following PPE:
A National Institute for Occupational Safety and
Health
(NIOSH)/Mine Safety and Health Administration
(MSHA)-
approved, N-series particulate respirator (i.e.,
chemical
mask) with a soft rubber face-to-mask seal and
replaceable
cartridges (49-51);
Splash-proof safety goggles;
Gauntlet neoprene gloves, which should be a minimum
length
of 12 inches (30.5 cm); and
Heavy-duty, acid-proof neoprene apron.
An eye wash station should be available and easily
accessible.
Exposure to fluoride chemicals
If the operator gets either wet or dry chemicals on the
skin, he
or she should thoroughly wash the contaminated skin area
immediately. If the operator's clothing is contaminated
with a wet
chemical, he or she should remove the wet contaminated
clothing
immediately. If the operator's clothing becomes
contaminated with
dry chemicals, he or she should change work clothing daily
no
later than the close of the work day (51).
Recommended Emergency Procedures For Fluoride Overfeeds
Fluoride overfeeds
When a community fluoridates its drinking water, a
potential
exists for a fluoride overfeed. Most overfeeds do not
pose an
immediate health risk; however, some fluoride levels
can be
high enough to cause immediate health problems. All
overfeeds
should be corrected immediately because some have the
potential
to cause serious long-term health effects (52-55).
Specific actions should be taken when equipment
malfunctions or
an adverse event occurs in a community public water
supply
system that causes a fluoride chemical overfeed
(Table_1)
(33).
When a fluoride test result is at or near the top end
of the
analyzer scale, the water sample must be diluted and
retested
to ensure that high fluoride levels are accurately
measured.
Ingested fluoride overdose
Persons who ingest dry fluoride chemicals and
fluorosilicic acid
should receive emergency treatment (Table_3 and
Table_4)
(10,56-62).
RECOMMENDATIONS FOR FLUORIDATED SCHOOL PUBLIC WATER SUPPLY SYSTEMS
Administration
School water fluoridation is recommended only when the school
has its
own source of water and is not connected to a community water
system.
Each state is responsible for determining whether school water
fluoridation is desirable and for effecting a written agreement
between
the state and appropriate school officials. A school water
fluoridation
program must not be started unless resources are available at
the state
level to undertake operational and maintenance responsibilities.
For
example, one full-time school technician should be assigned to
every
25-30 schools. The following recommendations should be
implemented for a
school water fluoridation program:
The state must take the primary responsibility for operating
and
maintaining school fluoridation equipment. School personnel
should be
responsible only for monitoring fluoride levels and minimal
operation
and maintenance of equipment.
For each school being considered for water fluoridation,
appropriate
state personnel should evaluate and prioritize the following
criteria:
Number of students who will benefit;
Natural fluoride level in the school's drinking water;
Recommended fluoride level of the community water systems
in the
geographic area where the students live;
Whether the water system for the entire school system (the
elementary, middle, and/or the high school) will be
fluoridated;
Technical feasibility of fluoridating the school's water
system;
and
Evaluation of the fluoride content of water drunk at home
by
students attending a school being considered for
fluoridation.
That evaluation must occur before school is selected. In
general,
if greater than 25% of the children attending the school
already
receive optimally fluoridated water at home, the school's
water
should not be fluoridated (31). None of the existing
research on
school water fluoridation covers prekindergarten children
(63-68).
At a minimum, state personnel should visit annually each
school
system and provide a thorough inspection and overhaul of the
equipment (usually during summer recess or when school is not
in
session).
The state must provide school administrative officials with
operating
procedures to follow should an overfeed occur. These
operating
procedures should address the following:
Shutting down the equipment;
Preventing the consumption of high fluoride concentrations
(greater than 10 mg/L) in the drinking water;
Notifying appropriate state personnel; and
Other emergency procedures.
Monitoring and Surveillance
For each school that has a fluoridated water system, a sample
of the
drinking water must be taken and analyzed for fluoride
content before
the beginning of each school day. Samples may be taken by
appropriate
school personnel. This sampling will not prevent fluoride
overfeeds
but will prevent consumption of high levels of fluoride.
School personnel must divide at least one sample per week,
with one
portion analyzed for fluoride at the school and the other
portion
analyzed at the state laboratory. The weekly state test
results
should be compared with test results obtained at the school
to ensure
that school personnel are using the proper analytic
techniques and
that their daily samples are being tested accurately for
fluoride.
Optimal fluoride levels in a school water system should be
established by the state (Table_5). (State regulations
supersede
recommendations provided in this report.)
Technical Requirements
General
School water fluoridation systems should be installed only
where
the water is supplied by a well pump with a uniform flow
because
varying flow rates can cause problems in consistently
maintaining
optimal fluoride levels (31).
All school water fluoridation systems should be built with
a
bypass arrangement so that the fluoridation equipment can
be
isolated during service and inspection periods without
shutting
off the school water supply. Most states use a pipe loop,
with
gate valves isolating such devices as the injection point,
meters,
strainers, check valves, make-up water, and take-off
fittings.
Fluoridation equipment should be placed in an area that is
secure
from tampering and vandalism.
A routine maintenance schedule should be established.
Items to be
checked include pump diaphragm, check valve, Y-strainers
or
sediment filters, injection points (for clogging), flow
switch
contacts and paddles, saturator tank (for cleaning),
pressure
switch, solenoid valve, float switch, and foot valve.
All hose connections within reach of the fluoride feed
equipment
should be provided with a hose bibb vacuum breaker.
Cross-connection control, in conformance with state
regulations,
must be provided.
State personnel should keep records on the amount of
fluoride used
at each school.
Sodium Fluoride Saturator Systems
Manually filled saturators should be used in all school
fluoridation systems. Upflow saturators generally are
recommended
because less maintenance is required. Make-up water (i.e.,
replacement water for the saturator) should be added
manually for
the following reasons:
Greater protection from an overfeed will be provided
because
only a finite amount of solution is available and no
continuously active (i.e., "hot") electrical outlet
will be
necessary; and
Potential problems with sticking solenoid valves are
eliminated.
The metering pump must be installed so that it cannot
operate
unless water is being produced (interlocked). For example,
the
metering pump must be wired electrically in series with
the flow
switch and the main well pump.
The metering pump must be plugged only into the circuit
containing
the overfeed protection; it must be physically impossible
to plug
the fluoride metering pump into any continuously active
("hot")
electrical outlet. The pump should be plugged only into
the
circuit containing the interlock protection. One method of
ensuring interlock protection is to provide on the
metering pump a
special, clearly labeled plug that is compatible only with
a
special outlet on the appropriate electrical circuit.
Another
method of providing interlock protection is to wire the
metering
pump directly into the electrical circuit that is tied
electrically to the well pump or service pump, so that
such hard
wiring can be changed only by deliberate action. These
methods are
especially important with an upflow saturator installation
because
a solenoid valve requires the continuously active ("hot")
electrical connection.
A flow switch, which is normally in the open position,
must be
installed in series with the metering pump and the well
pump so
that the switch must close to activate the metering pump.
Flow
switches should be properly sized and installed to operate
in the
flow range encountered at the school. It should be
installed
upstream from the fluoride injection point.
Metering pumps should be sized to feed fluoride near the
midpoint
of their range for greatest accuracy. Pumps should always
operate
between 30%-70% of capacity. Metering pumps that do not
meet
design specifications should not be installed in schools.
Oversized metering pumps should not be used because
serious
overfeeds can occur if settings on the pump are too high.
Conversely, undersized metering pumps can cause erratic
fluoride
levels.
The fluoride metering pump should be located on a shelf
not more
than 4 feet (1.2 m) higher than the lowest normal level of
liquid
in the saturator. Many manufacturers recommend that
metering pump
be located lower than the liquid level being pumped (i.e.,
flooded
suction). However, a flooded suction line is not
recommended in
water fluoridation.
The priming switch on the metering pump should be
spring-loaded to
prevent the pump from being started erroneously with the
switch in
the priming position.
Two diaphragm-type, antisiphon devices must be installed
in the
fluoride feed line when a metering pump is used. The
antisiphon
device should have a diaphragm that is spring-loaded in
the closed
position. These devices should be located at the fluoride
injection point and at the metering pump head on the
discharge
side. The antisiphon device on the head of the metering
pump
should be selected so that it will provide the necessary
back
pressure required by the manufacturer of the metering
pump.
All antisiphon devices must be dismantled and visually
inspected
at least once a year. Repair or replacement schedules
should
follow the manufacturer's recommendations. All antisiphon
devices
should be vacuum tested semiannually. Operation of a
fluoridation
system without a functional antisiphon device can lead to
a
serious overfeed.
Sediment filters (20 mesh) should be installed in the
water
make-up line going to the sodium fluoride saturators,
between the
softener and the water meter.
A flow restrictor with a maximum flow of 2 gallons (7.6 L)
per
minute should be installed on all upflow saturators.
In an upflow saturator, either an atmospheric vacuum
breaker must
be installed or a backflow preventor must be provided in
accordance with state or local requirements for
cross-connection
control. The vacuum breaker must be installed according to
the
manufacturer's recommendations.
A master meter on the school water service line and a
make-up
water meter on the saturator water line are required so
that
calculations can be made to confirm that the proper
amounts of
fluoride solution are being fed. These meters should be
read daily
and the results recorded.
A check valve should be installed in the main water line
near the
wellhead (in addition to any check valve included in the
submersible pump installation). The check valve should be
tested
at least annually for leakage.
The water used for sodium fluoride saturators should be
softened
whenever the hardness exceeds 50 ppm (or even less if
clearing
stoppages or removing scale becomes labor intensive). Only
the
water used for solution preparation (i.e., the make-up
water)
needs to be softened.
Unsaturated (i.e., batch-mixed) sodium fluoride solution
should
not be used in water fluoridation.
Only granular sodium fluoride should be used in saturators
because
both powdered and very fine sodium fluoride can cause
plugging in
the saturator.
The minimum depth of sodium fluoride in a saturator should
be 12
inches (30.5 cm). This depth should be externally marked
on the
saturator tank. The saturator should never be filled so
high that
the undissolved chemical is drawn into the pump suction
line.
All sodium fluoride chemicals must conform to the AWWA
standard
(B-701) to ensure that the drinking water will be safe and
potable
(43).
Testing Equipment
The colorimetric method (SPADNS) of fluoride analysis is
recommended for daily testing in school water
fluoridation. If
interferences are consistent (e.g., from iron, chloride,
phosphate, sulfate, or color), the final fluoride test
result can
be adjusted for these interferences. State laboratory
personnel
and the state school technician should reconcile the
interference
and make the appropriate adjustment.
Distillation is not needed when the colorimetric method
(SPADNS)
of fluoride analysis is used for testing daily fluoride
levels.
Safety Procedures
Fluoride remains a safe compound when maintained at the optimal
level in
the water supplied to a school water system; however, the school
technician could be exposed to excessive levels if proper
procedures are
not followed or if equipment malfunctions. Thus, the use of PPE
is
required when fluoride compounds are handled or when maintenance
is
performed on fluoridation equipment. The state should develop a
written
program for schools regarding the use of PPE.
Operator Safety
The state school technician should wear the following PPE:
A NIOSH/MSHA-approved, N-series particulate respirator
(i.e.,
chemical mask) with soft rubber face-to-mask seal and
replaceable cartridges (49-51);
Gauntlet neoprene gloves with cuffs, which should be a
minimum
of 12 inches (30.5 cm) long;
Splash-proof safety goggles; and
Heavy-duty, acid-proof neoprene apron.
An eye wash solution should be readily available and
easily
accessible.
Exposure to fluoride chemicals
If the operator gets dry chemicals on the skin, he or she
should
thoroughly wash the contaminated skin area immediately and
should
change work clothing daily no later than the close of the
work day
(51).
Recommended Emergency Procedures for Fluoride Overfeeds
Fluoride overfeeds
When a school system fluoridates its drinking water, a
potential
exists for a fluoride overfeed. Most overfeeds do not pose
an
immediate health risk; however, some can be high enough to
cause
immediate health problems. All overfeeds should be
corrected
immediately because some can cause long-term health
effects (52-55).
Specific actions should be taken when equipment
malfunctions or
an adverse event occurs that causes a fluoride chemical
overfeed in a school public water supply system
(Table_6).
When a fluoride test result is at or near the top end
of the
analyzer scale, the water sample must be diluted and
retested
to ensure that high fluoride levels are accurately
measured.
Ingested fluoride overdose
Persons who ingest dry fluoride chemicals should receive
emergency
treatment (Table_3) (10,56-62).
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Arnold FA Jr, Dean HT, Elvove E. Domestic water and dental
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Effect of increasing the fluoride content of a common water
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Dean HT, Arnold FA Jr, Elvove E. Domestic water and dental
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Russell AL, White CL. Dental caries in Maryland children after
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Russell AL, White CL. Dental caries in Maryland children after
seven
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Arnold FA Jr, Likins RC, Russell AL, Scott DB. Fifteenth year
of the
Grand Rapids fluoridation study. J Am Dent Assoc 1962;65:780-5.
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Ayers FJ. Fluoridation in Omaha, Nebraska: dental caries after
ten
years. The Chronicle (Omaha District Dental Society Journal)
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(Sept):1-4.
Chrietzberg JE, Lewis, JF. Effect of modifying the sub-optimal
fluoride
concentration in a public water supply. J Ga Dent Assoc
1962;(Jul):
12-17.
Reeves TG. Water fluoridation: a manual for engineers and
technicians.
Atlanta: US Department of Health and Human Services, Public
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Service, CDC, 1986.
Reeves TG. Water fluoridation: a manual for water plant
operators.
Atlanta: US Department of Health and Human Services, Public
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Service, CDC, 1994.
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fluoridation. In:
Pontius FW, ed. Water quality and treatment: a handbook of
community
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McKay FS. Mottled enamel: the prevention of its further
production
through a change of the water supply at Oakley, Idaho. J Am
Dent Assoc
1933;20:1137-49.
Dean HT, McKay FS, Elvove E. Mottled enamel survey of Bauxite,
Ark., 10
years after a change in the common water supply. Public Health
Rep
1938;53:1736-48.
McClure FS. Water fluoridation: the search and the victory.
Bethesda,
MD: US Department of Health and Human Services, Public Health
Service,
National Institutes of Health, National Institute of Dental
Research,
1970:7-16.
McKay FS. Mass control of dental caries through the use of
domestic
water supplies containing fluorine. Am J Public Health
1948;38:828-32.
Cox GJ, Matuschak MC, Dixon SF, Dodds ML, Walker WE.
Experimental
dental caries. IV. Fluorine and its relation to dental caries.
J Dent
Res 1939;18:481-90.
Dean HT, Jay P, Arnold FA Jr, Elvove E. Domestic water and
dental
caries. I. A dental caries study, including L. acidophilus
estimations,
of a population severely affected by mottled enamel and which
for the
past 12 years has used a fluoride-free water. Public Health Rep
1941;
56:365-81.
Environmental Protection Agency. Drinking water regulations,
amendments, fluoride. Federal Register 1979;44:42251.
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and
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Albany,
NY: Health Research, Inc., 1992.
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fluoride (B701-94). Denver: American Water Works Association,
1994:1-5.
American Water Works Association. ANSI/AWWA standard for sodium
fluorosilicate (B702-94). Denver: American Water Works
Association,
1994:1-5.
American Water Works Association. ANSI/AWWA standard for
fluorosilicic
acid (B703-94). Denver: American Water Works Association,
1994:1-5.
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1987;13:1-3.
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examination of water and wastewater. 18th ed. Washington, DC:
American
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AWWA manual M3. 4th ed. Denver, CO: American Water Works
Association,
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Ill Dent J 1993;62:165-9.
Li Y. Fluoride: safety issues. J Indiana Dent Assoc
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Disanayake JK, Abeygunasekara A, Jayasekara R, Ratnatunga C,
Ratnatunga
NV. Skeletal fluorosis with neurological complications. Ceylon
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1994;39:48-50.
Gessner BD, Beller M, Middaugh JP, Whitford GM. Acute fluoride
poisoning from a public water system. N Engl J Med
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345-9.
Church LE. Fluorides -- use with caution. J Md State Dent Assoc
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Baltazar RF, Mower MM, Reider R, Funk M, Salomon J. Acute
fluoride
poisoning leading to fatal hyperkalemia. Chest 1980;78:660-3.
Bayless JM, Tinanoff N. Diagnosis and treatment of acute
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Whitford GM. Acute and chronic fluoride toxicity. J Dent Res
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1249-54.
Horowitz HS, Law FE, Pritzker T. Effect of school water
fluoridation on
dental caries, St Thomas, V.I. Public Health Rep 1965;80:381-8.
Horowitz HS, Heifetz SB, Law FE, Driscoll WS. School
fluoridation
studies in Elk Lake, Pennsylvania, and Pike County, Kentucky --
results
after eight years. Am J Public Health 1968; 58:2240-50.
Horowitz HS. School water fluoridation. Am Fam Physician GP
1970;1:
85-9.
Horowitz HS, Heifetz SB, Law FE. Effect of school water
fluoridation on
dental caries: final results in Elk Lake, Pa, after 12 years. J
Am Dent
Assoc 1972;84:832-8.
Heifetz SB, Horowitz HS. Effect of school water fluoridation on
dental
caries: interim results in Seagrove, NC, after four years. J Am
Dent
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Heifetz SB, Horowitz HS, Brunelle JA. Effect of school water
fluoridation on dental caries: result in Seagrove, NC, after 12
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J Am Dent Assoc 1983;106:334-7.
Safe Drinking Water Act, 42 U.S.C. &300f et seq, as amended in
1986.
Glossary of Technical Terms
Adjusted fluoridated water system: A community public water system
that
adjusts the fluoride concentration in the drinking water to the
optimal
level for consumption (or within the recommended control
range).
Calculated dosage: The calculated amount of fluoride (mg/L) that
has been
added to an adjusted fluoridated water system. The calculation
is based
on the total amount of fluoride (weight) that was added to the
water
system and the total amount of water (volume) that was
produced.
Census designated place: A populated place, not within the limits
of an
incorporated place, that has been delimited for census purposes
by the
U.S. Bureau of the Census.
Check sample: A distribution water sample forwarded to either the
state
laboratory or to a state-approved laboratory for analysis.
Community: A geographical entity that includes all incorporated
places as
well as all census-designated places as defined by the U.S.
Bureau of
the Census.
Community public water system (CWS): A public water system that
serves at
least 15 service connections used by year-round residents or
that
regularly serves at least 25 year-round residents.
Consecutive water system: A public water system that buys water
from
another public water system. For purposes of water fluoridation
record
keeping, the consecutive water system should purchase at least
80% of
its water from a fluoridated water system.
Distribution sample: A water sample taken from the distribution
lines of
the public water system that is representative of the water
quality in
the water system.
Fluoridated water system: A public water system that produces water
that
has fluoride from either naturally occurring sources at levels
that
provide maximum dental benefits, or by adjusting the fluoride
level to
optimal concentrations.
Incorporated place: A populated place possessing legally defined
boundaries
and legally constituted government functions.
Monitoring, fluoride: The regular analysis and recording by water
system
personnel of the fluoride ion content in the drinking water.
Natural fluoride level: The concentration of fluoride (mg/L) that
is
present in the water source from naturally occurring fluoride
sources.
Naturally fluoridated water system: A public water system that
produces
water that has fluoride from naturally occurring sources at
levels that
provide maximum dental benefits.
Nontransient, noncommunity water system (NTNCWS): A public water
system
that is not a community water system and that regularly serves
at least
25 of the same persons more than 6 months per year.
Optimal fluoride level: The recommended fluoride concentration
(mg/L) based
on the annual average of the maximum daily air temperature in
the
geographical area of the fluoridated water system.
Overfeed, fluoride: Any fluoride analytical result above the
recommended
control range of the water system. Different levels of response
are
expected from the operator depending on the extent of the
overfeed
(Table_1 and Table_6).
Public water system (PWS): A system that provides piped water to
the public
for human consumption. To qualify as a public water system, a
system
must have 15 or more service connections or must regularly
serve an
average of at least 25 individuals 60 or more days per year.
Recommended control range: A range within which adjusted
fluoridated water
systems should operate to maintain optimal fluoride levels.
This range
is usually set by state regulation.
School technician: A state employee (usually from either the dental
or
drinking water program) whose primary responsibility is to
provide for
site visits, assist in the training of school fluoridation
monitors,
provide surveillance of all fluoridated school water systems,
and
resolve problems. This person functions as the water plant
operator for
a school fluoridation system and may be either an engineer or a
technician.
School water system: A nontransient, noncommunity water system that
serves
only a school.
Split sample: A distribution water sample taken by the water plant
operator, who analyzes a portion of the sample and records the
results
on the monthly operating report to the state. The operator then
forwards the remainder of the sample to the state laboratory or
to a
state-approved laboratory for analysis.
State: This term includes the 50 contiguous states and U.S.
territories.
State fluoridation administrator: A state employee (usually from
either the
dental or drinking water program) who is responsible for the
administration of the fluoridation program.
State fluoridation specialist: A state employee (usually from
either the
dental or drinking water program) whose primary responsibility
is to
provide for site visits, assist in the training of water plant
operators, provide surveillance of all fluoridated water
systems, and
resolve problems. This person may be either an engineer or a
technician.
Surveillance, fluoride: The regular review of monitored data and
split
sample or check sample results to ensure that fluoride levels
are
maintained by the community water systems in a specific
geographic
area. The review is conducted by a source independent of the
water
system.
Uniform flow: When the rate of flow of the water past a point
varies by
less than 20%.
Upstream: In a water line, a point closer to the source of water.
Water, make-up: Water that is used to replace the saturated
solution from a
sodium fluoride saturator; this saturated solution is pumped
into the
distribution lines.
Water fluoridation: The act of adjusting the fluoride concentration
in the
drinking water of a water system to the optimal level.
Exhibit A
The Association of State and Territorial Dental Directors
Instructions for Completing Fluoridation Quarterly Report for
Community and School Water Systems
Table_1 Note:
To print large tables and graphs users may have to change their printer settings to landscape and use a small font size.
TABLE 1. Recommended fluoride overfeed actions for community water systems, United States (31)
=============================================================================================================
Fluoride level Actions Recommended
-------------------------------------------------------------------------------------------------------------
0.1 mg/L above control range * to 2.0 mg/L 1. Leave the fluoridation system on.
2. Determine malfunction and repair.
2.1 mg/L to 4.0 mg/L 1. Leave the fluoridation system on.
2. Determine malfunction and repair.
3. Notify supervisor and report the incident to the
appropriate county or state agencies.
4.1 mg/L to 10.0 mg/L 1. Determine malfunction and immediately
attempt repair.
2. If the problem is not found and corrected quickly,
turn off the fluoridation system.
3. Notify supervisor and report the incident to the
appropriate county or state agencies.
4. Take water samples at several points in the
distribution system and test the fluoride content.
Retest if results are still high.
5. Determine malfunction and repair. Then, with
supervisor's permission, restart the fluoridation
system.
10.1 mg/L or greater + 1. Turn off the fluoridation system
immediately.
2. Notify supervisor and report the incident
immediately to the appropriate county or state
agencies and follow their instructions.
3. Take water samples at several points in the
distribution system and test the fluoride content.
Retest if results are still high. Save part of each
sample for the state laboratory to test.
4. Determine malfunction and repair. Then, with
supervisor's and the state's permission, restart
the fluoridation system.
-------------------------------------------------------------------------------------------------------------
* See control ranges in Table 2.
+ The state might require public notification to prevent consumption of high levels of fluoridated water.
=============================================================================================================
Table_2 Note:
To print large tables and graphs users may have to change their printer settings to landscape and use a small font size.
TABLE 2. Recommended optimal fluoride levels for community public water supply systems (31,32)
===================================================================================================
Annual average of maximum daily Recommended Recommended control range
air temperatures (8,9) fluoride (mg/L) 0.1-0.5
------------------------------- concentrations -------------------------
F C (mg/L) Below Above
---------------------------------------------------------------------------------------------------
50.0-53.7 10.0-12.0 1.2 1.1 1.7
53.8-58.3 12.1-14.6 1.1 1.0 1.6
58.4-63.8 14.7-17.7 1.0 0.9 1.5
63.9-70.6 17.8-21.4 0.9 0.8 1.4
70.7-79.2 21.5-26.2 0.8 0.7 1.3
79.3-90.5 26.3-32.5 0.7 0.6 1.2
---------------------------------------------------------------------------------------------------
* Based on temperature data obtained for a minimum of 5 years.
===================================================================================================
Table_3 Note:
To print large tables and graphs users may have to change their printer settings to landscape and use a small font size.
TABLE 3. Recommended emergency treatment for persons who ingest dry fluoride chemicals (NaF and Na2SiF6) (60)
===============================================================================================================
Milligrams fluoride ion (mg) ingested per
body weight (kg) * Treatment
---------------------------------------------------------------------------------------------------------------
<5.0 mg of fluoride ion/kg + 1. Give calcium (milk) orally to relieve
gastrointestinal symptoms. Observe for 2-4
hours. (A can of evaporated milk should
be available at all times to use for
emergency treatment.)
2. Induced vomiting is not necessary.
>=5.0 mg of fluoride ion/kg 1. Move the person away from any
contact with fluoride and keep him or her
warm.
2. Call the Poison Control Center.
3. If the person is conscious, induce vomiting
by rubbing the back of the person's throat
with either a spoon or your finger or giving
the person syrup of ipecac. To prevent
aspiration of vomitus, the person should be
placed face down with the head lower than the body.
4. Give the person a glass of milk or any
source of soluble calcium (i.e., 5% calcium
gluconate or calcium lactate solution).
5. Take the person to the hospital as quickly
as possible.
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* Average weight/age: 0-15 kg/0-2 years; 15-20 kg/3-5 years; 20-23 kg/6-8 years; 23-23-45 kg/9-15 years;
45-70 kg and higher/15-21 years and older.
+ 5 mg of fluoride (F) equals 11 mg of sodium fluoride (8 mg of sodium fluorosilicate). Ingesting 5 mg
F/kg is equivalent to a l54-lb. (70 kg) person consuming 0.8 grams of sodium fluoride (0.6 grams of sodium
fluorosilicate).
===============================================================================================================
Table_4 Note:
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TABLE 4. Recommended emergency treatment for persons who ingest fluorosilicic acid (H2SiF6) (60)
===============================================================================================================
Milligrams fluoride ion (mg)
ingested per body weight (kg) * Treatment
---------------------------------------------------------------------------------------------------------------
<5.0 mg fluoride/kg + 1. Give calcium (milk) orally to relieve
gastrointestinal symptoms. Observe for 2-4
hours. (A can of evaporated milk should be
available at all times to use for emergency
treatment.)
2. Induced vomiting is not necessary.
>=5.0 mg fluoride/kg 1. Move the person away from any contact
with fluoride and keep him or her warm.
2. Call the Poison Control Center.
3. If advised by the Poison Control Center and if
the person is conscious, induce vomiting by
rubbing the back of the person's throat with
a spoon or your finger or use syrup of ipecac.
To prevent aspiration of vomitus, the person
should be placed face down with the head lower than the
body.
4. Give the person a glass of milk or any source
of soluble calcium (i.e., 5% calcium gluconate
or calcium lactate solution).
5. Take the person to the hospital as quickly as
possible. It is important that whoever takes
the person to the hospital notify physicians
that the person is at risk for pulmonary edema
as late as 48 hours afterward.
---------------------------------------------------------------------------------------------------------------
* Average weight/age: 0-15 kg/0-2 years; 15-20 kg/3-5 years; 20-23 kg/6-8 years; 23-45 kg/9-15 years; 45-70 kg
and higher/15-21 years and older.
+ 5 mg of fluoride (F) equals 27 mg of 23% fluorosilicic acid. Ingesting 5 mg F/kg is equivalent to a l54-lb.
(70 kg) person consuming 2 grams of fluorosilicic acid.
===============================================================================================================
Table_5 Note:
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TABLE 5. Recommended optimal fluoride levels for school public water supply systems (31,32)
=============================================================================================
Annual average of maximum daily Recommended
air temperatures (8,9) fluoride Recommended control range (mg/L)
-------------------------------- concentrations --------------------------------
F C (mg/L) 20% Below 20% Above
---------------------------------------------------------------------------------------------
50.0-53.7 10.0-12.0 5.4 4.3 6.5
53.8-58.3 12.1-14.6 5.0 4.0 6.0
58.4-63.8 14.7-17.7 4.5 3.6 5.4
63.9-70.6 17.8-21.4 4.1 3.3 4.9
70.7-79.2 21.5-26.2 3.6 2.9 4.3
79.3-90.5 26.3-32.5 3.2 2.6 3.8
---------------------------------------------------------------------------------------------
* Based on temperature data obtained for a minimum of 5 years.
+ Based on 4.5 times the optimal fluoride level for communities.
=============================================================================================
Table_6 Note:
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TABLE 6. Recommended fluoride overfeed actions for school public water supply systems (31)
==========================================================================================================
Fluoride level Actions recommended
----------------------------------------------------------------------------------------------------------
0.1 mg/L above recommended control 1. Turn off the fluoridation system
range * to 10.0 mg/L immediately.
2. Notify state technician.
3. Notify supervisor.
4. Take water samples at several points in the school and
hold the samples for the state technician.
5. Follow advice of the state technician.
10.l mg/L or higher 1. Turn off the fluoridation system immediately.
2. Notify state technician.
3. Notify supervisor.
4. Take water samples at several points in the distribution
system and hold samples for the state technician.
5. Prevent the consumption of high levels of fluoridated water.
6. Follow advice of the state technician.
----------------------------------------------------------------------------------------------------------
* See Table 5 for the recommended control range.
==========================================================================================================
Table_A1 Note:
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Introduction
The purpose of this report is to provide data in summary form to
describe the quality of fluoridation in each state as determined by the
ability of fluoridating systems to conduct monitoring and maintain
optimal fluoride levels.
General Instructions
1. All community water systems in the state that adjust the fluoride
concentrations of their drinking water supply should be included in this
report.
2. The optimal fluoride level for a particular system is to be based on
the annual average of maximum daily air temperature for the geographic
area over a 5-year period.
Instructions for Completing Form
Item 1. Record the state name.
Item 2. Enter the quarter covered by the report. The reporting period is the
3-month quarter beginning in January, April, July, or October. Reports
are requested within 60 days after the end of reporting period.
Item 3. Provide an update on the following:
A. Record previous quarter's total systems and population.
B. The names of systems that began fluoridating during the quarter,
date started, and the total population served.
C. The names of systems that discontinued fluoridating during the
quarter, date discontinued, and the population that was served.
NOTE: This does not include systems with temporary interruption of
service. These fall into Item 4 or Item 5.
D. The total number of fluoridated systems at the end of the quarter
and the total population served.
Item 4. Report the total number of systems and population served that did not
report required sampling in any month of the reporting period as
determined by either or both of the following criteria:
Table_A2 Note:
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a. Split/check Samples (check samples are acceptable if split samples
are not available) should be included on the report if every
quarterly or monthly split sample was not submitted.
b. Monitoring Reports - For systems required to monitor daily by the
state, monitoring results were reported for less than 75 percent of
days water was pumped; or for systems required to monitor less
frequently, at least one monitoring result per week was not
reported.
Item 5. Report the total number of systems and population served that failed
to maintain optimal fluoride levels because of either of the following:
a. The mean of all fluoride verification samples, for each system, was
more than 0.1 ppm below or 0.5 ppm above the optimal fluoride level
for the system.
b. More than 25 percent of the monitoring samples, for each system,
were more than 0.1 ppm below or 0.5 ppm above the optimal level
(outliers). Report the number of systems and the population in
this category.
NOTE: Systems that fail to maintain optimal levels should only be in
Item 4 or Item 5-NOT BOTH.
Item 6. Report total number of systems and population served that have
maintained optimal levels for all 3 months in the quarter. Do not
include systems falling into Item 4 or Item 5 above.
Note: Items 4, 5, and 6 must equal End of Quarter total Item 3D.
Item 7. Report total number of systems and population served that had more
than one-third of the split/check samples taken in the quarter
deviating by more than plus or minus 0.2 ppm from the corresponding
monitoring results.
Note: Systems included in this item may also be included in Items 4,
5, and 6.
Table_A3 Note:
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FLUORIDATION QUARTERLY REPORT COMMUNITY WATER SYSTEMS
----------------------------------------------------------------
1. STATE: _________________2. REPORTING PERIOD: _______________
-----------------------------------------------------------------
3. END OF QUARTER STATISTICS:
A: Last Quarter Total Systems:________ Population:__________
B: Began During Quarter (one line)
NAMES DATE STARTED POPULATION SERVED
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
C: Discontinued During Quarter
NAMES DATE DISCONT. POPULATION SERVED
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
D: Total Systems Fluoridating
End of Quarter Total Systems:_______ Population:_________
-----------------------------------------------------------------
4. SUMMARY OF SYSTEMS WITH INCOMPLETE DATA
Number of Systems: __________ Population Served: ___________
-----------------------------------------------------------------
5. SUMMARY OF SYSTEMS NOT MEETING OPTIMAL LEVELS
Number of Systems: __________ Population Served: ___________
-----------------------------------------------------------------
6. SUMMARY OF SYSTEMS MEETING OPTIMAL LEVELS
Number of Systems: __________ Population Served: ___________
-----------------------------------------------------------------
7. SYSTEMS WITH INADEQUATE CORRELATION BETWEEN CHECK SAMPLES AND
MONITORING RESULTS
Number of Systems: __________ Population Served: ___________
-----------------------------------------------------------------
Person Completing
Form:___________________Telephone______________
Table_A4 Note:
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Introduction
The purpose of this report is to provide data in summary form to
describe the quality of fluoridation in each state as determined
by the ability of fluoridating schools to conduct monitoring and
maintain optimal fluoride levels.
General Instructions
1. All school water systems in the state that adjust the
fluoride concentrations of their drinking water supply should be
included in this report.
2. The optimal fluoride level for a particular system is to be
based on the annual average of maximum daily air temperature for
the geographic area over a 5-year period. This optimal fluoride
level is the community optimal level multiplied by 4.5 for use
in schools.
Instructions for Completing Form
Item 1. Record the state name.
Item 2. Enter the quarter covered by the report. The reporting
period is the 3-month quarter beginning in October, January, and
April. Reports are requested within 60 days after the end of
reporting period.
Item 3. Provide an update on the following:
A. Record previous quarter's total schools and population.
B. The names of schools that began fluoridating during the quarter,
date started, and the total population served.
C. The names of schools that discontinued fluoridating during the
quarter, date discontinued, and the population that was served.
NOTE: This does not include schools with temporary interruption of
service. These fall into Item 4 or Item 5.
D. The total number of fluoridated schools at the end of the quarter
and the total population served.
Item 4. Report the total number of schools and population served that did
not report required sampling in any month of the reporting period as
determined by either or both of the following criteria:
Table_A5 Note:
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a. Verification Sample - a school should be included on the
report if every weekly verification sample was not submitted.
b. Monitoring Reports - For systems required to monitor daily by
the state, monitoring results were reported for less than 75
percent of days water was pumped; or for systems required to
monitor less frequently, at least one monitoring result per week
was not reported.
Item 5. Report the total number of systems and population served
that failed to maintain optimal fluoride levels because of
either of the following:
a. The mean of all fluoride verification samples, for each
school, was more than 0.5 ppm below or 1.5 ppm above the optimal
fluoride level for the system.
b. More than 25 percent of the monitoring samples, for each
school, were more than 0.5 ppm below or 1.5 ppm above the
optimal level (outliers). Report the number of systems and the
population in this category.
NOTE: Schools that fail to maintain optimal levels should only
be in Item 4 or Item 5--NOT BOTH.
Item 6. Report total number of schools and population served
that have maintained optimal levels for all 3 months in the
quarter.
Do not include schools falling into Item 4 or Item 5 above.
Note: Items 4, 5, and 6 must equal End of Quarter total Item 3D.
Table_A6 Note:
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FLUORIDATION QUARTERLY REPORT SCHOOL WATER SYSTEMS
-----------------------------------------------------------------
1. STATE: _________________ 2. REPORTING PERIOD:_______________
-----------------------------------------------------------------
3. END OF QUARTER STATISTICS:
A: Last Quarter Total Schools:________ Population:__________
B: Began During Quarter (one line)
NAMES DATE STARTED POPULATION SERVED
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
C: Discontinued During Quarter
NAMES DATE DISCONT. POPULATION SERVED
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
_______________ ____________________ ___________________
D: Total Schools Fluoridating
End of Quarter Total Schools:_______ Population:_________
-----------------------------------------------------------------
4.SUMMARY OF SCHOOLS WITH INCOMPLETE DATA
Number of Schools: __________ Population Served: ___________
-----------------------------------------------------------------
5. SUMMARY OF SCHOOLS NOT MEETING OPTIMAL LEVELS
Number of Schools: __________ Population Served: ___________
-----------------------------------------------------------------
6. SUMMARY OF SCHOOLS MEETING OPTIMAL LEVELS
Number of Schools: __________ Population Served: ___________
-----------------------------------------------------------------
Person Completing
Form:___________________Telephone______________
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