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1.2 Addition

ADDITION: ADDING TO A SUM OR TOTAL

Addition is used when combining items, or putting items together to obtain a total. It helps answer questions such as "How many?" "How much?" or "How far?" Let's look at different ways that addition can be used. Some words used often to refer to addition are "plus", "and", "the sum of", "total", or "added to".

Example 1 - Pedro's crew has 4 pulaskis. Jane's crew has 6 pulaskis. How many pulaskis do they have together?

Addition Chart

As shown the the figure above, the addition needed to answer this question is: 4 + 6 = 10.
 

ADDITION IS USED IN COMBINING DISTANCES OR LENGTHS.

Example 2 - Crew 1 constructs 14 chains of handline on the day shift. Crew 2 constructs 11 chains of handline on the night shift. How many chains did crew 1 and 2 construct altogether?

14 chains + 11 chains = 25 chains

 

ADDITION IS USED TO FIND THE DISTANCE AROUND AN OBJECT.

The total distance around an object is called the perimeter.

Example 3 - The Division Supervisor (DIVS) used two dozers to construct a line. The dozers cleared a line of the following shape. How many chains of dozer line were constructed?
 

Addition Chart

45 chains + 36 chains + 28 chains + 29 chains + 110 chains = 248 chains

 

ADDITION IS USED IN COMBINING AREAS.

Example 4 - The day shift had two spot fires that were contained at 6 acres and 8 acres each. What was the total area of the spot fires that burned during the day shift?

6 acres + 8 acres = 14 acres

 

ADDITION IS USED IN COMBINING VOLUMES.

Example 5 - Herman pumped 30 gallons of fuel into one tank, 25 gallons into the next tank, and 27 gallons into the last tank. How many gallons of fuel did Herman pump?

30 gallons + 25 gallons + 27 gallons = 82 gallons

 

ADDITION IS USED IN COMBINING LARGER NUMBERS.

When adding several numbers, especially large numbers, add the ones (1s) first, then the tens (10s), then the hundreds (100s), and so on.

Example 6 - Add: 548 + 365
First, add the ones. There are 13 ones, or 1 ten and 3 ones. Write 3 in the ones column and "carry over" the 1 above the tens.
Next, add the tens. There are 11 tens, or 1 hundred and 1 ten. Write 1 in the tens column and the 1 above the hundreds.
Now, add the hundreds. There are 9 hundreds.addition of large numbers
The answer to 548 + 365 is 913.

ADDING POSITIVE AND NEGATIVE NUMBERS

Numbers can be positive or negative. Positive numbers are indicated with a + sign, or have no sign. If a number is written without a sign, the sign is assumed to be positive. Negative numbers are indicated with a - sign. For example, a negative pressure may be indicated as -25 inches of Hg, or as a vacuum of 25 inches of Hg. 

Signs are important in adding numbers. Here are some easy rules to help determine the sign of a sum: 
image tag sign rules for addition

Example 7 - Adding numbers with like signs.
5 + 5 = 10
3 + 3 = 6
-5 + (-5) = -10
-3 + (-3) = -6
 

Example 8 - Adding numbers with unlike signs. Notice that the sign of the larger number is the sign that the answer will have.
5 + (-3) = 2
3 + (-3) = 0
3 + (-5) = -2
2 + (-3) = -1

NWCG Latest Announcements

NWCG Risk Management Committee Releases Safety Bulletin: 24-001 Use of Respirators on Wildland Fires

Date: November 7, 2024
Contact: Risk Management Committee

The Risk Management Committee (RMC) has released Safety Bulletin: 24-001 Use of Respirators on Wildland Fires. As wildland fire respirators are available through several established vendors, wildland fire personnel need to understand regulations and limitations of respirator use in the workplace.

Safety Bulletin 24-001 outlines the following topics regarding respirator use for wildland fires:

  • Requirements for Respirator Use
  • Voluntary Respirator Use
  • Current Respirator Options
  • Unknown Risks of Respirator Use

This bulletin also provides mitigation recommendations to help reduce smoke exposure for wildland firefighting efforts.

References:

NWCG Safety Bulletin: 24-001 Use of Respirators on Wildland Fires

NWCG Smoke Management Guide for Prescribed Fire, PMS 420-3

VIDEO: Protecting Wildfire Personnel from Smoke - How Incident Management Teams Address Smokes Risks

VIDEO: Smoke, Knowing the Risks

The Incident Position Standards and Next Generation Position Task Book are now available for Medical Unit Leader (MEDL)

Date: October 16, 2024
Contact: Incident Medical Subcommittee

NWCG is excited to announce that the NWCG Incident Position Standards for Medical Unit Leader, PMS 350-39 and NWCG Position Task Book for Medical Unit Leader (MEDL), PMS 311-39 are now available.

The Performance Support Package, which for MEDL includes the Incident Position Standards and Next Generation Position Task Book, were developed through the Incident Performance and Training Modernization (IPTM) effort. The Performance Support Package will support trainees, those qualified in the position, and evaluators.

References:

NWCG Medical Unit Leader Position Page

NWCG Incident Position Standards for Medical Unit Leader, PMS 350-39

NWCG Position Task Book for Medical Unit Leader (MEDL), PMS 311-39

The Wildland Fire Learning Portal is Now Available

Date: October 9, 2024
Contact: Wildland Fire Learning Portal

The Wildland Fire Learning Portal (WFLP) is back online following a migration to a new learning management system (LMS) application. The WFLP team is actively addressing any issues that may arise as a result of the update, and appreciates your patience as the team works to enhance your experience. NWCG will share information from the WFLP as it is available.

Should you have any issues with accessing or using the WFLP, please use the link below to submit a ticket through the Help Center.

References:

Wildland Fire Learning Portal

Wildland Fire Learning Portal Help Center

NWCG Equipment Technology Committee Releases New Equipment Bulletins

Date: September 27, 2024
Contact: Equipment Technology Committee

The Equipment Technology Committee (ETC) has released three new Equipment Bulletins:

  • ETC-EB-24-003 Diesel exhaust fluid (DEF) in fuel containers.
  • ETC-EB-24-004 Two-compartment fuel and oil container (Dolmar) unavailable in the United States (US) and reminders for upkeeping current inventories.
  • ETC-EB-24-005 Personal Protective Equipment (PPE): Inspection, Care, and Maintenance.

These bulletins remind field going personnel of important issues related to equipment for wildland firefighting efforts.

References:

NWCG Alerts

ETC-EB-24-003 Diesel exhaust fluid (DEF) in fuel containers

ETC-EB-24-004 Two-compartment fuel and oil container (Dolmar) unavailable in the United States (US) and reminders for upkeeping current inventories

ETC-EB-24-005 Personal Protective Equipment (PPE): Inspection, Care, and Maintenance