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Chemical Datasheet

IODINE

8 - Corrosive 6.1 - Poison

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 7553-56-2
  • 3495
  • Corrosive
  • Poison
none
NIOSH Pocket Guide International Chem Safety Card
Iodine
  • IODINE
NFPA 704
data unavailable
General Description
Violet-black crystals with a metallic luster and a sharp odor. Mp: 133.5°C, bp: 185°C. Emits toxic vapor at room conditions; vapor becomes visibly purple when its concentration builds up in a confined space. Nearly insoluble in water but very soluble in aqueous solutions of iodides.

Hazards

Reactivity Alerts
none
Air & Water Reactions
No rapid reaction with air. No rapid reaction with water.
Fire Hazard
Excerpt from 154 Polymerizable warning [Substances - Toxic and/or Corrosive (Non-Combustible)]:

Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. For electric vehicles or equipment, 147 Polymerizable warning (lithium ion batteries) or 138 Polymerizable warning (sodium batteries) should also be consulted. (ERG, 2020)
Health Hazard
Excerpt from NIOSH Pocket Guide for Iodine:

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 (NIOSH, 2023)
Reactivity Profile
IODINE is an oxidizing agent. Reacts vigorously with reducing materials. Incompatible with powdered metals in the presence of water (ignites), with gaseous or aqueous ammonia (forms explosive products), with acetylene (reacts explosively), with acetaldehyde (violent reaction), with metal azides (forms yellow explosive iodoazides), with metal hydrides (ignites), with metal carbides (ignites easily), with potassium and sodium (forms shock-senstive explosive compounds) and with alkali-earth metals (ignites). Incompatible with ethanol, formamide, chlorine, bromine, bromine trifluoride, chlorine trifluoride.
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation
Excerpt from 154 Polymerizable warning [Substances - Toxic and/or Corrosive (Non-Combustible)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2020)
Firefighting
Excerpt from 154 Polymerizable warning [Substances - Toxic and/or Corrosive (Non-Combustible)]:

SMALL FIRE: Dry chemical, CO2 or water spray.

LARGE FIRE: Dry chemical, CO2, alcohol-resistant foam or water spray. If it can be done safely, move undamaged containers away from the area around the fire. Dike runoff from fire control for later disposal.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. (ERG, 2020)
Non-Fire Response
Excerpt from 154 Polymerizable warning [Substances - Toxic and/or Corrosive (Non-Combustible)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS. (ERG, 2020)
Protective Clothing
Excerpt from NIOSH Pocket Guide for Iodine:

Skin: PREVENT SKIN CONTACT - Wear appropriate personal protective clothing to prevent skin contact.

Eyes: PREVENT EYE CONTACT - Wear appropriate eye protection to prevent eye contact.

Wash skin: WHEN CONTAMINATED - The worker should immediately wash the skin when it becomes contaminated.

Remove: WHEN WET OR CONTAMINATED - Work clothing that becomes wet or significantly contaminated should be removed and replaced.

Change: DAILY - Workers whose clothing may have become contaminated should change into uncontaminated clothing before leaving the work premises.

Provide:
• EYEWASH (>7%) - Eyewash fountains should be provided in areas where there is any possibility that workers could be exposed to the substances; this is irrespective of the recommendation involving the wearing of eye protection. (>7%)
• QUICK DRENCH (>7%) - Facilities for quickly drenching the body should be provided within the immediate work area for emergency use where there is a possibility of exposure. [Note: It is intended that these facilities provide a sufficient quantity or flow of water to quickly remove the substance from any body areas likely to be exposed. The actual determination of what constitutes an adequate quick drench facility depends on the specific circumstances. In certain instances, a deluge shower should be readily available, whereas in others, the availability of water from a sink or hose could be considered adequate.] (>7%) (NIOSH, 2023)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Iodine 7553-56-2 Solid >480
> indicates greater than.

Special Warning from DuPont: Tychem® and Tyvek® fabrics should not be used around heat, flames, sparks or in potentially flammable or explosive environments. Only...

(DuPont, 2023)

First Aid
Excerpt from NIOSH Pocket Guide for Iodine:

Eye: IRRIGATE IMMEDIATELY - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: SOAP WASH IMMEDIATELY - If this chemical contacts the skin, immediately wash the contaminated skin with soap and water. If this chemical penetrates the clothing, immediately remove the clothing, wash the skin with soap and water, and get medical attention promptly.

Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible.

Swallow: MEDICAL ATTENTION IMMEDIATELY - If this chemical has been swallowed, get medical attention immediately. (NIOSH, 2023)

Physical Properties

Chemical Formula:
  • I2
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: 236°F (NIOSH, 2023)
Vapor Pressure: 0.3 mmHg at 77°F (NIOSH, 2023)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 4.93 (NIOSH, 2023) - Denser than water; will sink
Boiling Point: 365°F at 760 mmHg (NIOSH, 2023)
Molecular Weight: 253.8 (NIOSH, 2023)
Water Solubility: 0.01 % (NIOSH, 2023)
Ionization Energy/Potential: 9.31 eV (NIOSH, 2023)
IDLH: 2 ppm (NIOSH, 2023)

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

Chemical ERPG-1 ERPG-2 ERPG-3
Iodine (7553-56-2) 0.1 ppm star-in-circle icon indicates that odor should be detectable near ERPG-1. 0.5 ppm 5 ppm
star-in-circle icon indicates that odor should be detectable near ERPG-1.
(AIHA, 2022)

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Iodine (7553-56-2) 0.1 ppm 0.5 ppm 5 ppm
(DOE, 2018)

Regulatory Information

EPA Consolidated List of Lists

No regulatory information available.

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names