NIOSH Pocket Guide to Chemical Hazards


CAS 7553-56-2


RTECS NN1575000
Synonyms & Trade Names
Iodine crystals, Molecular iodine
DOT ID & Guide


NIOSH REL: C 0.1 ppm (1 mg/m3)
OSHA PEL: C 0.1 ppm (1 mg/m3)
IDLH 2 ppm See: 7553562 Conversion 1 ppm = 10.38 mg/m3
Physical Description
Violet solid with a sharp, characteristic odor.
MW: 253.8
BP: 365°F
MLT: 236°F
Sol: 0.01%
VP(77°F): 0.3 mmHg
IP: 9.31 eV

Sp.Gr: 4.93
Fl.P: NA

Noncombustible Solid
Incompatibilities & Reactivities
Ammonia, acetylene, acetaldehyde, powdered aluminum, active metals, liquid chlorine
Measurement Methods
NIOSH 6005; OSHA ID212
See: NMAM or OSHA Methods
Personal Protection & Sanitation (See protection)
Skin: Prevent skin contact
Eyes: Prevent eye contact
Wash skin: When contaminated
Remove: When wet or contaminated
Change: Daily
Provide: Eyewash (>7%), Quick drench (>7%)
First Aid (See procedures)
Eye: Irrigate immediately
Skin: Soap wash immediately
Breathing: Respiratory support
Swallow: Medical attention immediately
Important additional information about respirator selection
Respirator Recommendations NIOSH/OSHA
Up to 1 ppm:
(APF = 10) Any supplied-air respirator*
Up to 2 ppm:
(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
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted acid gas 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
Exposure Routes inhalation, ingestion, skin and/or eye contact
Symptoms Irritation eyes, skin, nose; lacrimation (discharge of tears); headache; chest tightness; skin burns, rash; cutaneous hypersensitivity
Target Organs Eyes, skin, respiratory system, central nervous system, cardiovascular system
See also: INTRODUCTION   See ICSC CARD: 0167   See MEDICAL TESTS: 0121