What Is the Ozone layer?

No, ozone is not the bull's eye on a target! In fact, it's nothing you can see. Ozone is a naturally occuring gas found on the earth's atmosphere. At the outer edge of the atmosphere there is a thin layer of ozone gas that is critical to life on earth. It is the stratospheric ozone layer. This layer protects us from the harmful rays of the sun. If it weren't for the ozone layer, we'd get wicked sunburn, wreck our eyes, and kill our plants.

What Causes Reductions Of The Ozone Layer?


When certain chemicals used on earth escape into the atmosphere they are broken down by solar radiation and release chlorine and bromine atoms which, in a chainreaction, destroy ozone molecules. This reaction ocures more frequently than natural ozone replenishment, resulting in a thinning of the ozone layer.

Is The Ozone Layer Threatened?

Atmospheric measurements tell us that the ozone layer is getting thinner, and that at certain times of the year an ozone layer "hole" appears over Antarctica. Some people believe this reduction is due to solar or volcanic activity, but most scientists believe that certain man-made chemicals are major contributors to the problem. These chemicals include the chlorofluorocarbons (CFCs) found in refrigerators, solvents and blowing agents for foams, and the halons used for fire fighting.
Who Uses Halons?

Historically, the largest single user of halon has been the electronics industry. The protection of vital electronics facilities, such as computer rooms and communications rooms, is estimated to account for 65% of Halon 1301 use. The US Government uses halon for military applications (in ships, aircraft and tanks), for protecting fragile historical documents such as the Bill of Rights, and even protection of the President's limousine. Halons are also used extensively in oil production, electric power generation, and are required on all commercial passenger aircraft. Manufacturers who make everything from dolls to cars use halon to protect their personnel and products.

How Long Has Halon Been Used For Fire Protection?

Carbon tetrachloride (Halon 104) was used prior to 1900, even though its combustion by-products were lethal. Due to a number of deaths, a search for something safer began. Several other halons were tried, but it was not until 1947 that research by the Purdue Research Foundation and the US Army resulted in the discovery of two effective low toxicity halons: 1211 and 1301. When used properly, these halons have an excellent fire fighting record with little, if any, risk.

How Damaging Is Halon?

A compound's ability to destroy ozone depends on many factors, including the amount of chlorine and/or bromine that it contains. To aid them in comparing compounds, scientists have developed a relative scale called the ozone depletion potential (ODP). Common refrigerants, like those found in your refrigerator and in your car air conditioner, have been assigned the value 1 as a reference. Halon 1301 has the value between 10 and 16, meaning it has 10-16 times the more potential for destroying the ozone layer.

Halon use worldwide is significantly less than that of CFCs, so even though it is more damaging to the ozone layer, there is not as much of it released into the atmosphere. In fact, it is estimated that overall halons account for less than 20% of ozone depletion.
What Alternatives Are There?

There are a number of traditional fire extinguishing agents, such as water, carbon dioxide, dry chemicals, and foam that are good alternatives to halons for many applications. In addition, recent research has led to the commercialization of new agents and technologies. These fall into four basic categories: halocarbon compounds; inert gas mixtures; water-mist or fogging systems; and powdered aerosols. The growing list of alternatives to halon, in conjunction with advanced detection and fire resistant materials, provides protection from a broad spectrum of potential hazards. For more information on halon replacement agents, see the March 1996 report (revision 12) of the EPA Questions and Answers on Halon and their Substitutes, or contact HARC.

What Is HARC?

The Halon Alternatives Research Corporation (HARC) was formed to focus efforts for finding suitable alternatives for the halons used in fire fighting. It is also the major industry association providing information to the user community on halon-related issues. HARC has facilitated and encouraged the involvement of the fire protection community in environmentally responsible activities, including:

Coordinated development of an Industry Code of Practice for the best use of recycled halon.
Assisted in development of EPA Public Education Brochures.
Sponsored major conferences on aviation fire safety and alternative technologies.
Sponsored workshop on toxicological issues related to halocarbon replacements.
Sponsored research on halon bank management leading to the formation of the Halon Recycling Corporation (HRC).
HARC is now in its seventh year, and during that time has developed a unique, cooperative working relationship with government agencies concerned with the halon/CFC issue. For more information contact HARC at the telephone or fax numbers listed in this brochure.


Can Halon Be Recycled?

Unlike aluminum cans or newspapers, once halon is released it is virtually impossible to recover. If halon is still contained in cylinders retired from service or if a container is leaking, the halon can be recovered for reuse. In fact, some halon distributors and users have been doing this for many years, long before halon emissions were identified as an environmental problem. Current legislation prohibits the production or importation of new Halon 1211, 1301, or 2402 into the US Recycled halon is now the only source of supply.

It can be obtained from a number of sources, including fire equipment distributors and independent recylclers. Industry, in conjunction with EPA, formed a non-profit organization to assist in halon recycling. The Halon Recycling Corporation (HRC) acts as a facilitating organization by providing information services to match companies who have a surplus of halon with those companies who have an ongoing need for the fire fighting agent. For more information contact HRC at the telephone or fax number listed in this brochure.