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Chemical Datasheet

CALCIUM HYPOCHLORITE

5.1 - Oxidizer

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 7778-54-3
  • 1748
  • Oxidizer
none
NIOSH Pocket Guide International Chem Safety Card
none
  • CALCIUM HYPOCHLORITE
NFPA 704
Diamond Hazard Value Description
0
3 1
ox
Blue Health 3 Can cause serious or permanent injury.
Red Flammability 0 Will not burn under typical fire conditions.
Yellow Instability 1 Normally stable but can become unstable at elevated temperatures and pressures.
White Special OX Possesses oxidizing properties.
(NFPA, 2010)
General Description
A white granular solid (or tablets compressed from the granules) with an odor of chlorine. Toxic, irritating to the skin. Noncombustible, but will accelerate the burning of combustible materials. Prolonged exposure to fire or heat may result in the vigorous decomposition of the material and rupture of the container. Diluted samples may undergo reactions as described above if they contain less than 39% available chlorine but take longer to become involved and react less vigorously. Used for water purification, disinfectant for swimming pools, for bleaching paper and textiles.

Hazards

Reactivity Alerts
Air & Water Reactions
Water soluble. Slowly decomposed by water with the evolution of gaseous chlorine and heat.

Experimental work at Argonne National Laboratory has determined that there is essentially no Cl2 gas formation; the substance is quite unreactive in water. This does not prevent Cl2 formation by a catalytic mechanism, but under normal conditions calcium hypochlorite is quite unreactive. The hydration reaction was rapid and quite exothermic. The small change in gas volume was attributed to this heating. (Argonne Report ANL/DIS-00-1, October 2000).
Fire Hazard
Excerpt from ERG Guide 140 [Oxidizers]:

CAUTION: Ammonium nitrate products may explode if involved in fire or contaminated with hydrocarbons (fuels), organic matter, other contaminants or when hot molten and contained. Treat as an explosive (ERG Guide 112). These substances will accelerate burning when involved in a fire. Some may decompose explosively when heated or involved in a fire. May explode from heat or contamination. Some will react explosively with hydrocarbons (fuels). May ignite combustibles (wood, paper, oil, clothing, etc.). Containers may explode when heated. Runoff may create fire or explosion hazard. (ERG, 2024)
Health Hazard
Excerpt from ERG Guide 140 [Oxidizers]:

Inhalation, ingestion or contact (skin, eyes) with vapors or substance may cause severe injury, burns or death. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may cause environmental contamination. (ERG, 2024)
Reactivity Profile
CALCIUM HYPOCHLORITE is a powerful oxidizing agent, particularly in the presence of water or as it decomposes when heated to release oxygen and chlorine gases. May react vigorously with carbon; reacts potentially explosively with finely divided carbon. Reacts with acetylene to form explosive chloroacetylenes. Reactions with organic matter, oil, hydrocarbons; alcohols may lead to explosions. Reactions with nitromethane, methanol, ethanol (and other alcohols) can become violent after a delay. Reacts with possible ignition and/or explosion with organic sulfur compounds and with sulfides. Decomposes evolving oxygen, a change that can be catalyzed by rust on metal containers. Forms highly explosive NCl3 on contact with urea or ammonia. Evolves highly toxic gaseous chlorine gas when heated or on contact with acids [Sax, 9th ed., 1996, p. 1905]. A mixture with damp sulfur reacted violently, and molten sulfur was ejected [Chem Eng. News, 1965, 46(29), 6]. The combination of calcium hypochlorite, sodium hydrogen sulfate, starch, and sodium carbonate, when compressed, caused the materials to incandescence, followed by explosion, [Ind. Eng. Chem., 1937, 15, 282].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below.

Response Recommendations

Isolation and Evacuation
Excerpt from ERG Guide 140 [Oxidizers]:

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.

LARGE SPILL: Consider initial downwind evacuation for at least 100 meters (330 feet).

FIRE: If tank, rail tank car or highway tank 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. If ammonium nitrate products are in a tank, rail car or truck and involved in a fire, ISOLATE for 1600 meters (1 mile) in all directions; also, initiate evacuation including emergency responders for 1600 meters (1 mile) in all directions. (ERG, 2024)
Firefighting
Excerpt from ERG Guide 140 [Oxidizers]:

SMALL FIRE: Use water. Do not use dry chemicals or foams. CO2 or Halon® may provide limited control.

LARGE FIRE: Flood fire area with water from a distance. Do not move cargo or vehicle if cargo has been exposed to heat. If it can be done safely, move undamaged containers away from the area around the fire.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: For ammonium nitrate products: Do not fight cargo fire. Withdraw, evacuate and isolate area for at least 1600 meters (1 mile). Treat as an explosive (ERG Guide 112). Do not enter area for 24 hours or until expert advice has been provided. Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. ALWAYS stay away from tanks in direct contact with flames. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2024)
Non-Fire Response
Excerpt from ERG Guide 140 [Oxidizers]:

Keep combustibles (wood, paper, oil, etc.) away from spilled material. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Do not get water inside containers.

SMALL DRY SPILL: With clean shovel, place material into clean, dry container and cover loosely; move containers from spill area.

SMALL LIQUID SPILL: Use a non-combustible material like vermiculite or sand to soak up the product and place into a container for later disposal.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. (ERG, 2024)
Protective Clothing
Excerpt from ERG Guide 140 [Oxidizers]:

Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE. Structural firefighters' protective clothing provides thermal protection but only limited chemical protection. (ERG, 2024)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
Excerpt from ERG Guide 140 [Oxidizers]:

Refer to the "General First Aid" section. Specific First Aid: Contaminated clothing may be a fire risk when dry. (ERG, 2024)

Physical Properties

Chemical Formula:
  • Ca(ClO)2
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: data unavailable
Vapor Pressure: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity: data unavailable
Boiling Point: data unavailable
Molecular Weight: data unavailable
Water Solubility: data unavailable
Ionization Energy/Potential: data unavailable
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Calcium hypochlorite; (Calcium oxychloride) (7778-54-3) 2.6 mg/m3 28 mg/m3 170 mg/m3
(DOE, 2024)

Regulatory Information

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Calcium hypochlorite 7778-54-3 10 pounds

(EPA List of Lists, 2024)

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