EPA requires RISK MANAGEMENT PLANS for facilities with 2500 lbs. or more chlorine gas. RMPs are not required for the other forms of chlorine despite higher exposure rates and explosion hazards.
Department of Homeland Security
Currently, Water and Waste Treatment facilities are exempt, but this could change
Chemical Facility Anti-Terrorism Standards
For some reason, the hypochlorites (bleach and calcium hypochorite) are not included in spite of a higher accident rate:
The false impression that Chlorine Gas is less safe along with the absence of government regulation of hypochlorites, leads many operations to make the mistake of changing.
The RMP's required for Chlorine Gas may in themselves make Chlorine Gas the safest choice.
THE TRUE HAZARDS
Calcium Hypochlorite (Ca(OCI)2)
Dry, white or yellow-white, granular material produced from the reaction of lime and chlorine
Can ignite or explode on contact with organic materials (oil, rags, or alcohol), and it should not be exposed to fire or elevated temperatures
National Association of State Fire Marshals Catastrophic Fire Prevention Task Force recognizes a homeland security concern: oxidizers such as calcium hypochlorite could be used in chemical weapons developed by terrorists to cause fires, explosions, casualties and the general disruption of the economy.
Sodium Hypochlorite (NaOCI)
A water-based solution of sodium hydroxide and chlorine
Degradation of sodium hypochlorite is a problem* (In warmer climates, it degrades even more rapidly.)
*White, George Clifford, Handbook of Chlorination, Van Nostrand, 1992
Can be explosive when mixed with acids
Center for Disease Control Homemade Chemical Bomb Events and Resulting Injuries (July 2003 report) A total of 29 Home Chemical Bomb events were reported during 1993 2003. 83% in the last two years of the study. 59% involved sodium hypochlorite. In October 2001, a high school student placed a chemical bomb in a vacant classroom. The bomb, made with sodium hypochlorite, released chlorine gas on explosion. A total of 23 persons in the vicinity of the explosion sustained respiratory irritation and were transported to a hospital for treatment.
General Negatives of Hypochlorites
They are readily available and falsely regarded as safe Potentially explosive Containers of hypochlorite are easier to contaminate than cylinders of gas The absence of risk management plans and chemical security plans could actually make these facilities more vulnerable
Switching to Other Forms of Chlorine Doesn't Make Gas Chlorine Go Away, It Simply Moves it to Another Place
On Feb. 12, 2007, nearly 900 pounds of chlorine vaporized into greenish clouds after a Tideflats, WA bleach plant worker accidentally released the deadly chemical from a pressurized tank. Ambulances took about 25 people, including 12 firefighters, to Tacoma emergency rooms for treatment for exposure to the deadly gas.
On-Site Bleach Generation Is Not Without Its Hazards
Hydrogen gas is generated and is Highly Explosive Crossville, TN April 13, 2004 Blast kills city worker (Crossville Chronicle, April 14, 2004) Palm Beach County, FL January 4, 2008 Equipment explosion (Palm Beach Post, April 14, 2008) Article refers to 6 prior explosions at other facilities