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OSHA/EPA Occupational Chemical Database

Chemical Identification
Chemical Name: CHLORINE DIOXIDE
CAS #: 10049-04-4 UN No: Formula: ClO2
Synonyms: Chlorine oxide; Chlorine peroxide

Physical Properties
Physical Description: Yellow to red gas or a red-brown liquid (below 52ºF) with an unpleasant odor similar to chlorine and nitric acid.
BP: 52ºF MW: 67.5 LEL: NA NFPA Fire Rating: NA
FRZ/MLT: FRZ: -74ºF VP: >1 atm UEL: NA NFPA Health Rating: NA
FP: NA (Gas) ? (Liquid) VD: 2.33 NFPA Reactivity Rating: NA
Sp. GR: 1.6 (Liquid at 32ºF) IP: 10.36 eV NFPA Sp. Inst.: NA

Exposure Limits
OSHA NIOSH Related Information
PEL-TWA ppm: 0.1 REL-TWA ppm: 0.1 AIHA Emergency Response Planning Guidelines - ERPG-1/ERPG-2/ERPG-3:
NA/0.5 ppm/3 ppm
PEL-TWA mg/m3: 0.3 REL-TWA mg/m3: 0.3
PEL-STEL ppm: NA REL-STEL ppm: 0.3
PEL-STEL mg/m3: NA REL-STEL mg/m3: 0.9
PEL-C ppm: NA REL-C ppm: NA
PEL-C mg/m3: NA REL-C mg/m3: NA Carcinogen Classifications: NA
Skin Notation: No Skin Notation: No
Notes: NA Notes: NA

IDLH ppm: NA

IDLH mg/m3: 5

IDLH Notes: NA

NIOSH Pocket Guide to Chemical Hazards (Current through June 2006)
Chlorine dioxide CAS: 10049-04-4
Formula: ClO2 RTECS: FO3000000
Synonyms & Trade Names: Chlorine oxide, Chlorine peroxide DOT ID & Guide: 9191 143 (hydrate, frozen)
Exposure Limits
NIOSH REL: TWA 0.1 ppm (0.3 mg/m3) ST 0.3 ppm (0.9 mg/m3) OSHA PEL : TWA 0.1 ppm (0.3 mg/m3)
IDLH: 5 ppm Conversion: 1 ppm = 2.76 mg/m3
Physical Description
Yellow to red gas or a red-brown liquid (below 52F) with an unpleasant odor similar to chlorine and nitric acid. 
MW: 67.5 BP: 52F FRZ: -74F Sol(77F): 0.3%
VP: >1 atm IP: 10.36 eV RGasD: 2.33 Sp.Gr: 1.6 (Liquid at 32F)
Fl.P: NA (Gas) ? (Liquid) UEL: ? LEL: ? MEC: NA
Flammable Gas/Combustible Liquid (See flammable and combustible liquid classes)
Incompatibilities & Reactivities
Organic materials, heat, phosphorus, potassium hydroxide, sulfur, mercury, carbon monoxide [Note: Unstable in light. A powerful oxidizer.]
Measurement Methods
OSHA ID126SGX, ID202
Personal Protection & Sanitation First Aid
Skin: Prevent skin contact (liquid)
Eyes: Prevent eye contact (liquid)
Wash skin: When contam (liquid)
Remove: When wet (flamm)
Change: N.R.
Provide: Eyewash (liquid), Quick drench (liquid)
Eye: Irr immed (liquid)
Skin: Soap wash immed (liquid)
Breath: Resp support
Swallow: Medical attention immed (liquid)
(See procedures)
NIOSH Respirator Recommendations
NIOSH/OSHA 1 ppm: CCRS/SA 2.5 ppm: SA:CF/PAPRS 5 ppm: CCRFS/GMFS/SCBAF/SAF : SCBAF:PD,PP/SAF:PD,PP:ASCBA Escape GMFS/SCBAE
(See symbols and codes)
Exposure Routes
Inh Ing (liquid) Con
Symptoms
Irrit eyes, nose, throat; cough, wheez, bron, pulm edema; chronic bron
(See abbreviations)
Target Organs
Eyes, resp sys
(See abbreviations)

DOT Emergency Response Guidebook (ERG 2004)
Guide Number: 143
143 Oxidizers (Unstable)
POTENTIAL HAZARDS
FIRE OR EXPLOSION
*       May explode from friction, heat or contamination.
*       These substances will accelerate burning when involved in a fire.
*       May ignite combustibles (wood, paper, oil, clothing, etc.).
*       Some will react explosively with hydrocarbons (fuels).
*       Containers may explode when heated.
*       Runoff may create fire or explosion hazard.
HEALTH
*       TOXIC; inhalation, ingestion or contact (skin, eyes) with vapors,
        dusts or substance may cause severe injury, burns, or death.
*       Fire may produce irritating and/or toxic gases.
*       Toxic fumes or dust may accumulate in confined areas (basement,
        tanks, hopper/tank cars, etc.).
*       Runoff from fire control or dilution water may cause pollution.
PUBLIC SAFETY
*       CALL Emergency Response Telephone Number on Shipping Paper first. If
        Shipping Paper not available or no answer, refer to appropriate
        telephone number listed on the inside back cover.
*       Isolate spill or leak area immediately for at least 50 to 100 meters
        (160 to 330 feet) in all directions.
*       Keep unauthorized personnel away.
*       Stay upwind.
*       Keep out of low areas.
*       Ventilate closed spaces before entering.
PROTECTIVE CLOTHING
*       Wear positive pressure self-contained breathing apparatus (SCBA).
*       Wear chemical protective clothing which is specifically recommended by
        the manufacturer. It may provide little or no thermal protection.
*       Structural firefighters' protective clothing provides limited
        protection in fire situations ONLY; it is not effective in spill
        situations.
EVACUATION
Spill
*       See the Table of Initial Isolation and Protective Action Distances for
        highlighted substances. For non-highlighted substances, increase, in
        the downwind direction, as necessary, the isolation distance shown
        under PUBLIC SAFETY.
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.
EMERGENCY RESPONSE
FIRE
Small Fires
*       Use water.  Do not use dry chemicals or foams.  CO2 or Halon may
        provide limited control.
Large Fires
*       Flood fire area with water from a distance.
*       Do not move cargo or vehicle if cargo has been exposed to heat.
*       Move containers from fire area if you can do it without risk.
*       Do not get water inside containers: a violent reaction may occur.
*       Cool containers with flooding quantities of water until well after
        fire is out.
*       Dike fire-control water for later disposal.
*       ALWAYS stay away from tanks engulfed in fire.
*       For massive fire, use unmanned hose holders or monitor nozzles; if this
        is impossible, withdraw from area and let fire burn.
SPILL OR LEAK
*       Keep combustibles (wood, paper, oil, etc.) away from spilled material.
*       Do not touch damaged containers or spilled material unless wearing
        appropriate protective clothing.
*       Use water spray to reduce vapors or divert vapor cloud drift.
*       Prevent entry into waterways, sewers, basements or confined areas.
Small Spills
*       Flush area with flooding quantities of water.
Large Spills
*       DO NOT CLEAN-UP OR DISPOSE OF, EXCEPT UNDER SUPERVISION OF A
        SPECIALIST.
FIRST AID
*       Move victim to fresh air.
*       Call 911 or emergency medical service.
*       Apply artificial respiration if victim is not breathing.
*       Administer oxygen if breathing is difficult.
*       Remove and isolate contaminated clothing and shoes.
*       In case of contact with substance, immediately flush skin or eyes with
        running water for at least 20 minutes.
*       Keep victim warm and quiet.
*       Ensure that medical personnel are aware of the material(s) involved,
        and take precautions to protect themselves.
ERG 2004 Isolation and Protective Distances
 
       SMALL SPILLS           |       LARGE SPILLS
(From a small package or      | (From a large package or
small leak from a large pkg.) | from many small packages)
  First    |     Then         |  First    |      Then
 ISOLATE   |    PROTECT       | ISOLATE   |     PROTECT
  in all   |persons Downwind  |  in all   | persons Downwind
Directions |    during-       |Directions |     during-
           |DAY       NIGHT   |           | DAY        NIGHT
Chlorine dioxide, hydrate, frozen (when spilled in water)
100 ft     0.1 mi     0.1 mi     100 ft     0.1 mi     0.4 mi
ERG 2004 Toxic-by-Inhalation (TIH) Gas(es) Produced When Spilled in Water
TIH: Cl2

Additional Emergency Response Information (CAMEO Data)
Non-fire Spill Response: NA
Firefighting: NA
Reactivity: Organic materials, heat, phosphorus, potassium hydroxide, sulfur, mercury, carbon monoxide
First Aid: Eyes: Irrigate immediately (liquid); Skins: Soap wash immediately (liquid); Inhalation: Respiratory support; Ingestion: Medical attention immediately (liquid)




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