Cal Fire Develops a High-heat Resistant Ember PreScreen from Centri Precleaner to Protect Health of Crew and Longevity of Engines
Fire dozer engine air intake systems are vulnerable to high heat and burning embers associated with wildland fire suppression. Original Equipment Manufacturer, (OEM) pre-cleaners melt under high heat exposure and do not provide burning ember protection as recommended by the National Fire Protection Association, (NFPA).
Inadequate ember protection can allow burning embers to enter the air filter housing and ignite the air filter that will cause the engine to stall out. Loss of engine power can put the equipment operator in extreme danger.
Cal Fire worked with DRM Diversafab, (formerly BEST-EX, INC.) manufacturer of the “Centri™” precleaner to develop a high heat resistant precleaner and ember prescreen that would meet the engine OEM air intake requirements, meet the NFPA and Cal Fire Fix-N-Fax #42 requirement of preventing burning embers larger than 0.039 inch from reaching the air filter.
DRM Diversafab was successful in their development of a “High Heat” model precleaner and a “High Heat” model prescreen to prevent any chance of a burning ember larger than .036 inch from reaching the paper air filter to comply with NFPA. The maximum temperature tolerance of the precleaner is 1,200 degrees Fahrenheit. The grease in the bearings is only good to approximately 350 degrees Fahrenheit for short duration but bearing failure will not compromise ember protection during a burn over. The prescreen made with the Kevlar® thread (locking stitching) is 900 degrees Fahreheit. The Silicone coating (gray color) on the fabric is 500 degrees Fahrenheit and the Fiberglass base fabric is 1,000 degrees Fahreheit.
In 2008, CAL FIRE was able to secure Federal Grant Funds (CFAA/SFA) to equip each CAL FIRE bull dozer with a high heat resistant precleaner and ember prescreen. In February of 2009 all CAL FIRE dozers were provided with pre-cleaner kits appropriate for the make/model dozer and it is required to have the provided pre-cleaner installed on by April 15, 2009.