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Chemical Datasheet

CALCIUM HYPOCHLORITE, HYDRATED MIXTURE, WITH NOT LESS THAN 5.5% BUT NOT MORE THAN 16% WATER

5.1 - Oxidizer 8 - Corrosive

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 7778-54-3
  • 3487 (corrosive)
  • 2880
  • Oxidizer
  • Corrosive
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
Calcium hypochlorite, hydrated is a white granular solid or tablets compressed from the granules having an odor of chlorine. It is noncombustible, but it will accelerate the burning of combustible materials. It is decomposed by water with evolution of chlorine gas and heat. Prolonged exposure to fire or heat may result in the vigorous decomposition of the material and rupture of the container. Material containing less than 39% available chlorine may undergo reactions as described above though it may take longer to initiate, and the resulting reactions may not be as vigorous. It is used for water purification, disinfectant for swimming pools, for bleaching paper and textiles, and for many other uses.

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 140 Polymerizable warning [Oxidizers]:

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, 2020)
Health Hazard
Excerpt from 140 Polymerizable warning [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, 2020)
Reactivity Profile
CALCIUM HYPOCHLORITE, HYDRATED MIXTURE is a powerful oxidizing agent, particularly in the presence of water or at higher temperature as it decomposes to release oxygen and chlorine gases. As strong oxidant it may react with vigor in combination with carbon, especially finely divided is explosive; acetylene, leads to creation of explosive chloroacetylenes; organic matter, oil, hydrocarbons; alcohols may cause explosion, methanol, ethanol, etc.; nitromethane caused delayed violent reaction; organic sulfur compounds, sulfides tend toward ignition and sometimes explosion; with iron oxide in metal containers catalyze oxygen evolving decomposition of the oxidant. It forms highly explosive NCl3 on contact with urea. Produces highly toxic gaseous chlorine gas when heated or on contact with acids [Sax, 9th ed., 1996, p. 1905]. Mixture of damp sulfur with hypochlorite caused a violent reaction, that ejected molten sulfur, Chem Eng. News, 1965, 46(29), 6.
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 140 Polymerizable warning [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 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. If ammonium nitrate is in a tank, rail car or tank 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, 2020)
Firefighting
Excerpt from 140 Polymerizable warning [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 OR CAR/TRAILER LOADS: 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 engulfed in fire. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2020)
Non-Fire Response
Excerpt from 140 Polymerizable warning [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, 2020)
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, 2020)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
Excerpt from 140 Polymerizable warning [Oxidizers]:

Call 911 or emergency medical service. Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air if it can be done safely. Give artificial respiration if victim is not breathing. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. Contaminated clothing may be a fire risk when dry. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. Keep victim calm and warm. (ERG, 2020)

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, 2018)

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, 2022)

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