Wildland Firefighting (3rd Edition)
Chapter 2 - Fire Apparatus & Communication Equipment for Wildland Fires
"By the Numbers"
- NFPA 1901, Standard for Automotive Fire Apparatus, contains requirements for structural fire engines.
- Minimum pump volume capacity is 750 gpm, however,2,000 gpm pumps are not uncommon today.
- Minimum water tank size is 500 gallons, however, 1,000 gallon tanks are not uncommon today.
- Apparatus with tanks larger than 1,000 gallons are considered mobile water apparatus.
- Initial attack fire apparatus must have a capacity of 250 gpm. Typically it carries 100 to 300 gallons of water and has 3 to 5 crew members.
- In regards to resource typing, Type 1 engines have a crew of 4, a 1,000 gpm pump, and 1,200 feet of 2 1/2 inch hose, while Type 2 engines have a crew of 3, a 500 gpm pump, and 1,000 feet of 2 1/2 inch hose. All figures are minimums.
- Type 1 and 2 engines are used as structural engines, while Type 3 and 4 are typically brush or wildland engines.Type 5, 6, and 7 engines are rarely used (also referred to as patrols).
- Most auxiliary engine-driven (15 to 50 horsepower) pumps have capacities less than 500 gpm.
- Mobile water supply apparatus have engine-driven pumps with capacities up to 1,250 gpm.
- Midship transfer drive pumps commonly range from 1,000 to 2,000 gpm, however, capacities up to 6,000 gpm are available.
- Most engines can only draft water from about 20 feet below the pump and only at about 60% of the rated capacity.
- In flashy fuels with high heat output or long flame length, 1 1/2 inch hose should be used for safety.
- Short lengths (5 to 20 feet) of booster hose attached to the front, rear, or sides of the apparatus allows personnel to walk along with the apparatus and apply water or foam.
- Booster lines should not be extended with unlined 1 inch forestry hose, except during mop-up operations.
- Remote control nozzles are capable of flows from 10 to 300 gpm.
- Baffles inside water tanks must extend from wall to wall and cover at least 75% of the area spanned.
- The fill opening/vent on the top of a water tank must be able to accommodate a 2 1/2 inch hose and coupling.
- Covered tank openings must be designed so that they will blow off when tank pressure exceeds 2 psi.
- The tank fill line from pump to tank must be at least 1 inch in diameter.
- When figuring gross vehicle weight, tank weight (with water) estimation is 10 pounds per gallon, personnel is 190 lbs. per person, and weight of fire equipment is also estimated.
- Gasoline engines are susceptible to stalling on slopes greater than 35%.
- NFPA 1906, Standard for Wildland Fire Apparatus, requirements:
Covers requirements, construction, and design for wildland apparatus.
Requires wildland apparatus to carry a minimum of 150 gallons of water.
Requires that the difference in weight on each axle (side to side) does not exceed 7% difference when the vehicle is fully loaded.
Requires that vehicles have a center of gravity no higher than 75% of the rear track width, on flat ground.
Requires fuel tanks to be large enough for the apparatus to pump at full capacity for at least 2 hours.
Prevents firefighters from riding outside a cab while the vehicle is in motion.
Specifies the distance from the ground to the first step of a wildland apparatus not exceed 24 inches with subsequent steps no farther than 18 inches apart. Steps should have a depth of 8 inches and a maximum surface area of 35 square inches (skid-resistant). If a ladder is used to access the top of the apparatus, it must be at least 7 inches away from the body of the apparatus. All steps must be capable of supporting 500 pounds.
- Any apparatus compartment greater than 2 1/2 cubic feet must be weather-resistant.
- Most wildland apparatus carry 10 to 100 gallons of Class A foam concentrate.
- Class A foam concentrate is typically proportioned at 0.1% to 1% of the total volume of the fire stream.
- In the mid-1980's, the U.S. Bureau of Land Management (BLM) conducted research that led to the development of high-energy Class A foam.
- Apparatus fighting structural or wildland fires using Compressed Air Foam Systems (CAFS) do so with an airflow rate of 0.5 cfm to 1 cfm per gallon of foam solution.
- 2 cfm per gallon of foam concentrate will produce a dry foam with an expansion ratio of 10:1 for flows up to 100 gpm.
- NFPA 1500, Standard on Fire Department Occupational Safety and Health Program, contains standards related to apparatus safety.
- When backing an apparatus, the alarm must be at least 87 decibels. Technical requirements can be found in SAE J994, Alarm Backup Electric Performance, Test, and Application by the Society of Automotive Engineers.
- Markings (unit letters/numbers) on tops of apparatus should be at least 2 feet in size.
- Minimum equipment for wildland apparatus:
Quantity / Item
1 / Axe
1 / Round-pointed shovel
2 / Handlights
1 / Fire extinguisher (minimum rating 40 B:C)
2 / Spanners
200 feet / Hose
1 / Nozzle
1 / First-Aid kit
1 / Hand-pump water extinguisher
2 / Wheel chocks
- Water tenders have pumps ranging from 50 to 300 gpm and tank capacities from 1,000 to 5,000 gallons. (page 73) **DISCREPANCY** Page 74 states water tenders have fire pumps ranging from 200 gpm auxiliary engine-driven pumps to 5,000 gpm midship-transfer drive pumps.
- NFPA 1231, Standard on Water Supplies for Suburban and Rural Fire Fighting, covers water shuttle operations.
- It may be possible for a water tender to refill as many as 20 wildland apparatus before needing to refill itself.
- Quick-dump piping on water tenders is generally at least 8 inches in diameter.
- NFPA 1231 states that converting tank vehicles designed for another purpose to mobile water supply apparatus is not recommended.
- Some engines are equipped with a 50 to 75 foot aerial ladder or elevated master stream device.
- Referring to bulldozers, Type 1 is known as heavy, Type 2 is medium, and Type 3 is a light dozer.
- A dozer can construct a single-pass fireline approximately 1/2 mph over moderate terrain and in medium fuel.
- A Type 2 tractor plow can cut a 6 foot wide fireline at a rate of 1 mph. A Type 1 is 2 mph.
- In paracargo drops, the drop zone is a strip 200 feet wide on each side of the flight path, 300 feet short of the target in the direction of approach, and 1,300 feet after the target in the direction of the aircraft's exit.
- Do not mark target areas for air drops within 600 feet of the incident base.
- An air drop target should be marked with a "T" at least 7 feet long. For multiple drops, a number should be placed below and to the right of the "T". The top of the "T" should be toward the wind.
- Fireground communications involves everything from face-to-face oral communication to 800 MHz radios.
- Most modern radios can transmit and receive on at least 32 frequencies and up to 200 or more.
- Most portable radios have 1 to 5 watts of transmitting/receiving power compared to the 100 to 150 watt mobile radio.
- Portable radio communication with another portable may be less than 1 mile.
- Newer portable radios are capable of handling up to 210 channels.
- Most modern CB radios have 40 channels.
- Global Positioning Systems (GPS) can generally determine the location of a vehicle within 100 feet.