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3.1 Volume or Capacity

Volume is used to indicate the capacity of a tank or container. It is used by firefighters to answer questions like "How much water is left in the tank?" and "At 15 gallons per minute (gpm), how many more minutes before the tank is empty?" 

VOLUME OF A RECTANGULAR OBJECT

The volume of a rectangular container is determined by multiplying the length (l) by the width (w) by the height (h).

volume

Volume = length × width × height
V = l × w × h

Example 1 - Determine the volume of the tank in gallons.

Example 1 Image

Step 1. Use the equation for determining the volume of a rectangle. V = l × w × h

Step 2. Identify the length, width, and height. l = 5 ft, w = 6 ft, h = 8 ft

Step 3. Set up the problem and solve. V = 5ft × 6ft × 8ft = (5 × 6 × 8) (ft × ft × ft) = 240 ft3

Step 4. Determine the appropriate conversion factor. 1 cubic foot = 7.4805 gallons

Step 5. Set up the cancellation table so all units will cancel except gallons (see Section 2.1).

Cancellation Table

The volume of the tank of water is 240 cubic feet or 1,795 gallons.

Example 2 - The water tank on a newly designed engine is 34 inches wide, 5 feet high, and 12 feet long. What is the capacity of the water tank in cubic feet? In gallons?

Example 2 image

Step 1. Use the equation for determining the volume of a rectangle. V = l × w × h

Step 2. Identify the length, width, and height. l = 12 ft, w = 34 in, h = 5 ft

Step 3. Convert all the measurements to the same units, feet.

Inches to Feet
Step 4. Set up the problem, and solve for volume. V = 2.83 ft × 5 ft × 12 ft = 170 ft3

Step 5. Set up the cancellation table so all units will cancel, except the desired unit, gallons.

Ft3 to Gallons

The volume of the tank is 170 cubic feet or 1272 gallons.

VOLUME OF A CYLINDER

The volume of a cylinder is found by multiplying the area of the base times the height, h. The base of a cylinder is a circle, A = π × r2, where π = 3.14. 

Volume Example

Example 3 - A cylindrical tank of foam concentrate is 5 feet tall. The tank diameter is 2.5 feet. What is the capacity, in gallons, of the tank?

Step 1. Use the equation for determining the volume of a cylinder.
V = π r2 × h

Step 2. Draw a sketch. Label the height and diameter.

Height and Diameter

π = 3.14, r = 1/2 d = 1/2 × 2.5 ft = 1.25 ft, h = 5 ft

Step 3. Set up the problem and solve. V = 3.14 × (1.25 ft)2 × 5 ft = 24.5 ft3

Step 4. Set up the cancellation table so all units will cancel, except the desired unit, gallons.

Ft3 to Gallons

The tank capacity is 183.3 gallons.

 

NWCG Latest Announcements

IBC Memo 24-01: OF 297 Signature Order and 2024 Fire Season Use IBC Memo 24-02: Summary of Changes for SIIBM, PMS 902

Date: July 15, 2024
Contact: Incident Business Committee 

The NWCG Incident Business Committee (IBC) has recently released two memorandums. The first provides direction on the use of the Emergency Equipment Shift Ticket, OF 297 for the 2024 fire season. Due to delays in hard copy printing, both the 2024 revision and the older version of the Emergency Equipment Shift Ticket, OF 297 are acceptable for use during the 2024 fire season.

The second memorandum documents the updates of the newly revised NWCG Standards for Interagency Incident Business Management (SIIBM), PMS 902. The summary of changes attached to the memo covers the major updates and process changes from the 2022 version.

References:

IBC Memorandum 24-01: OF 297 Signature Order and 2024 Fire Season Use

IBC Memorandum 24-02: Summary of Changes for the NWCG Standards of Interagency Incident Business Management, PMS 902

IBC Memorandum 24-02 Attachment: Summary of Changes

NWCG Standards for Rapid Extraction Module Support, PMS 552

Date: July 10, 2024
Contact: Incident Medical Unit Subcommittee 

A new publication from the Incident Medical Unit Subcommittee is now available. The NWCG Standards for Rapid Extraction Module Support, PMS 552 will be used as a guide and as an opportunity to begin to build out Rapid Extraction Module Support (REMS) modules for the remainder of Fire Year 2024. These standards will be fully implemented as the minimum standard starting in January 2025.

NWCG Standards for Rapid Extraction Module Support outlines the roles, duties, qualifications, and equipment pertinent to REMS. A REMS team, strategically stationed at wildland fires, plays a pivotal role in prioritizing swift access and medical treatment to injured or ill firefighters for safe and efficient egress off the fireline. This ensures their rapid transport to definitive medical care in cases of emergency during firefighting operations, highlighting the invaluable contribution of the REMS team to firefighter safety and well-being.

References:

NWCG Standards for Rapid Extraction Module Support, PMS 552

National Wildland Firefighter Day

Date: July 2, 2024
Contact: National Interagency Fire Center 

The National Wildfire Coordinating Group (NWCG) would like to recognize July 2, 2024, as National Wildland Firefighter Day (NWFFD). Established in 2022, NWFFD honors the dedication of wildland firefighters and support personnel. This day falls within the 2024 Week of Remembrance (June 30 - July 6), providing an opportunity to renew our commitment to wildland firefighter safety while remembering those who have fallen in the line of duty.

NWCG continues to provide leadership to enable interoperable wildland fire operations among federal, state, local, Tribal, and territorial partners. NWCG standards and training establish common practices to contribute to safe, effective, and coordinated national interagency wildland fire operations.

References:

NWCG.gov

Week of Remembrance

National Wildland Firefighter Day

2024 Week of Remembrance

Date: June 27, 2024
Contact: 6 Minutes for Safety Subcommittee 

As we approach the 2024 Week of Remembrance (WOR), June 30 to July 6, we dedicate this time to thoughtfully reviewing and recognizing the events of the 2018 Mendocino Complex. As such, this year’s theme of “Learning From the Mendocino Complex” embodies a longstanding hallmark of WOR, honoring through learning.

Throughout the week, our energy will be directed toward fostering generative conversations in briefing rooms and at tailgates.

References:

6 Minutes for Safety - 2024 Week of Remembrance

Wildland Fire Lessons Learned Center