- Author
- Verdonik, D. P. | Laramee, S. T. | DiNenno, P. J. | Williams, F. W.
- Title
- U.S. Navy Halon 1211 Replacement Plan. Part 3. Halon 1211 Mission Critical Reserve Evaluation.
- Coporate
- Hughes Associates, Inc., Baltimore, MD Naval Research Laboratory, Washington, DC
- Report
- NRL/MR/6180-99-8412, November 1, 1999, 115 p.
- Keywords
- halon 1211 | halon alternatives | fire fighting | fire fighting agents | aircraft crash equipment
- Abstract
- The U.S. Navy currently uses five firefighting agents for suppressing fires on flight lines and flight decks: water, Aqueous Film Forming Foam (AFFF), Halon 1211, potassium bicarbonate (PKP), and carbon dioxide (CO2) [NATOPS]. While each of these agents is potentially effective for flammable liquids or other combustibles typically encountered on flight lines and flight decks, each has advantages or disadvantages for a particular application. AFFF and water are the primary agents while PKP, Halon 1211, and. CO2 are secondary agents used with the primary agent or alone. The secondary agent is used alone in those situations where the primary agent is not effective and cannot completely extinguish the fire. It is often used in combination with the primary agent when increased effectiveness is required. For example, while AFFF is very effective in fighting pool fires and providing cooling, it is limited in fighting three- dimensional and deep seated, hidden fires. The three secondary agents are better than AFFF in fighting three-dimensional fires and hidden fires but do not provide effective cooling or burnback protection. An important distinction between the five agents is the potential for causing collateral damage or damage caused by the agent to hot metal surfaces, electronics, or avionics. Halon 1211 is recognized as the agent that will cause the least collateral damage. While Halon 1211 and CO2 may, in some extreme circumstances, both be considered 'clean,' CO2 may cause collateral damage due to thermal shock or static discharge. PKP and AFFF are not clean agents and may cause considerable collateral damage. For this reason, Halon 1211 has become the agent of choice in many aviation firefighting applications. The ability to reduce or eliminate collateral damage has been thought to be particularly important for engine fires and internal electrical fires. The aircraft may be placed back into service more quickly and at a lower cost when solely Halon 1211 is used to extinguish the fire.