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Phthalic anhydride

Synonyms & Trade Names
1,2-Benzenedicarboxylic anhydride, PAN, Phthalic acid anhydride
CAS No.
85-44-9
RTECS No.
TI3150000
DOT ID & Guide
2214 156
Formula
C₆H₄(CO)₂O
Conversion
1 ppm = 6.06 mg/m3
IDLH
60 mg/m3
See: 85449
Exposure Limits
NIOSH REL
TWA 6 mg/m3 (1 ppm)
OSHA PEL
TWA 12 mg/m3 (2 ppm) See Appendix G
Measurement Methods
NIOSH S179 (II-3);
OSHA 90
See: NMAM or OSHA Methods
Physical Description
White solid (flake) or a clear, colorless, mobile liquid (molten) with a characteristic, acrid odor.
Molecular Weight
148.1
Boiling Point
563°F
Melting Point
267°F
Solubility
0.6%
Vapor Pressure
0.0015 mmHg
Ionization Potential
10.00 eV
Specific Gravity
1.53 (Flake) 1.20 (Molten)
Flash Point
305°F
Upper Exposive Limit
10.5%
Lower Explosive Limit
1.7%
Combustible Solid
Incompatibilities & Reactivities
Strong oxidizers, water [Note: Converted to phthalic acid in hot water.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, upper respiratory system; conjunctivitis; nasal ulcer bleeding; bronchitis, bronchial asthma; dermatitis; In Animals: liver, kidney damage
Target Organs
Eyes, skin, respiratory system, liver, kidneys
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:Daily
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap wash promptly
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH

Up to 30 mg/m3:
(APF = 5) Any quarter-mask respirator.
Click here for information on selection of N, R, or P filters.*

Up to 60 mg/m3:
(APF = 10) Any particulate respirator equipped with an N95, R95, or P95 filter (including N95, R95, and P95 filtering facepieces) except quarter-mask respirators. The following filters may also be used: N99, R99, P99, N100, R100, P100.
Click here for information on selection of N, R, or P filters.*
(APF = 10) Any air-purifying full-facepiece respirator equipped with an N95, R95, or P95 filter. The following filters may also be used: N99, R99, P99, N100, R100, P100.
Click here for information on selection of N, R, or P filters.
(APF = 25) Any powered, air-purifying respirator with a high-efficiency particulate filter.*
(APF = 10) Any supplied-air respirator*
(APF = 50) Any self-contained breathing apparatus with a full facepiece

Emergency or planned entry into unknown concentrations or IDLH conditions:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus

Escape:
(APF = 50) Any air-purifying, full-facepiece respirator with an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0315   MEDICAL TESTS: 0192

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