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Maleic anhydride

Synonyms & Trade Names
cis-Butenedioic anhydride; 2,5-Furanedione; Maleic acid anhydride; Toxilic anhydride
CAS No.
108-31-6
RTECS No.
ON3675000
DOT ID & Guide
2215 156
Formula
C4H2O3
Conversion
1 ppm = 4.01 mg/m3
IDLH
10 mg/m3
See: 108316
Exposure Limits
NIOSH REL
: TWA 1 mg/m3 (0.25 ppm)
OSHA PEL
: TWA 1 mg/m3 (0.25 ppm)
Measurement Methods

NIOSH 3512;
OSHA 25 , 86
See: NMAM or OSHA Methods
Physical Description
Colorless needles, white lumps, or pellets with an irritating, choking odor.
MW:
98.1
BP:
396°F		 MLT: 127°F
Sol:
Reacts
VP:
0.2 mmHg
IP:
9.90 eV
Sp.Gr:
1.48
Fl.P:
218°F
UEL:
7.1%
LEL:
1.4%
Combustible Solid, but may be difficult to ignite.
Incompatibilities & Reactivities
Strong oxidizers, water, alkalis, metals, caustics & amines above 150°F [Note: Reacts slowly with water (hydrolyzes) to form maleic acid.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation nose, upper respiratory system; conjunctivitis; photophobia (abnormal visual intolerance to light), double vision; bronchial asthma; dermatitis
Target Organs
Eyes, skin, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin: Prevent skin contact
Eyes: Prevent eye contact
Wash skin: When contaminated
Remove: When wet or contaminated
Change: No recommendation
Provide: Eyewash
First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Soap wash immediately
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations

NIOSH/OSHA

Up to 10 mg/m3:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode£
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator 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 (gas mask) with a chin-style, front- or back-mounted organic vapor canister having 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   See ICSC CARD: 0799   See MEDICAL TESTS: 0256
 

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