PhostrEx is a fire suppression agent developed for use in aviation applications to replace halon, a

greenhouse gas A greenhouse gas (GHG or GhG) is a gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor (), carbon dioxide (), methane ...

(GHG). It was developed by Eclipse Aviation for use aboard their

Eclipse 500 The Eclipse 500 (model EA500) is a very light jet (VLJ) originally produced by Eclipse Aviation of Albuquerque, New Mexico, United States. The company was founded in 1998 to develop the 1997 Williams V-Jet II demonstrator. The prototype firs ...

very light jet A very light jet (VLJ), entry-level jet or personal jet, previously known as a microjet, is a category of small business jets seating four to eight people. VLJs are considered the lightest business jets and are approved for single-pilot operati ...

s as an engine fire suppression system, and is now being marketed to other aviation manufacturers.

Overview

The PhostrEx fire suppression system addresses many of the problems with halon, from system weight to environmental concerns. These concerns, including halon's ozone-depleting and global warming characteristics, prompted the

Montreal Protocol The Montreal Protocol is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances that are responsible for ozone depletion. It was agreed on 16 September 1987, and entered into force ...

to outlaw its use. The only exception allowed by this international treaty was in aviation applications, and only until a suitable replacement became available. PhostrEx meets the requirements of both the

and the Clean Air Act, and is the first commercially viable

Federal Aviation Administration The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic ...

and

United States Environmental Protection Agency The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it ...

certified halon replacement fire extinguishing agent. The EPA awarded the company with a 2007 Stratospheric Ozone Protection Award for the development of its PhostrEx fire-suppression system. PhostrEx reacts very quickly with atmospheric moisture, breaking down into phosphorus acid and

hydrogen bromide Hydrogen bromide is the inorganic compound with the formula . It is a hydrogen halide consisting of hydrogen and bromine. A colorless gas, it dissolves in water, forming hydrobromic acid, which is saturated at 68.85% HBr by weight at room tem ...

. Neither of these harms the

ozone layer The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in rel ...

. High concentrations of PhostrEx can cause skin blistering and eye irritation, however low concentrations are typically used due to its effectiveness. Any persons with skin or eye contact with PhostrEx should rinse the affected area with water as soon as possible. PhostrEx is not very corrosive to metals, but it can tarnish.

Spectrum Aeronautical Spectrum Aeronautical is a business jet developer based in Carlsbad, California with its development center located in Spanish Fork, Utah. An engine failure while flying a single-engine Stinson Voyager over the jungles of Honduras in 1958 nearly k ...

will incorporate the PhostrEx fire suppression system into its future aircraft.

Problems with halon

Most fire extinguishing agents pose a corrosion hazard to aircraft. The extinguishing effect of Halon is through interference of the thermal balance of the flame, and to a small extent by interfering with the chemical reaction of the fire. Halons are

chlorofluorocarbons Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are fully or partly halogenated hydrocarbons that contain carbon (C), hydrogen (H), chlorine (Cl), and fluorine (F), produced as volatile derivatives of methane, ethane, and propa ...

which cause damage to the

. It is being phased out for environmentally friendlier alternatives. However, most of these alternatives will not fit in an aircraft engine. Halon is mildly toxic in confined spaces.

Strengths

*More effective than halon by weight *Less weight by system *Lower maintenance costs *Environmentally friendly *FAA certified *EPA certified

Weaknesses

*In the presence of moisture, phosphorus tribromide is highly corrosive to most metals except lead and nickel."Demise of Eclipse opens the field for mx service"
By Matt Thurber, Aviation International News, May 1, 2009 *while applied during ground operation, it can harm passenger or fire fighter *Proprietary system

References

External links