White Mtn. Apache Fire & Rescue
March 2012 Monthly Training
FIREFIGHTING FOAM
The follow evolutions and/or training are to be completed for all suppression members
prior to March 30, 2012. Please review any applicable standard operating guidelines, the
Northern Arizona Interagency Training Committee’s (NAITC) and the White Mountain
Apache Fire & Rescue’s (WMAFR) Minimum Company Standards, and any attached
information for the technical requirements of each evolution.
The training shall be completed by each member and documented on the attached
“Training Completion Form”. This form shall be signed by the immediate supervisor
(Captain) and sent to the Deputy Fire Chief to be included in the training file.
Please note that this is the minimum training requirements for the month. As such, you
may (and it is recommended) that additional training topics be covered. Any WMAFR
MCS are practice, until officially evaluated.
Resources
To complete the following training each member/crew will need to secure the following
resources:
 SOG/SOP Manual
 WMAFR & NAITC MCS Booklet
 Fully equipped Type I Engine w/ In-Line Foam Eductor
 Residential structure, commercial structure(s), fire station or other
appropriate drill site.
 IFSTA Essentials of Firefighting, 4th Edition
 Class A or B Foam (old stuff if you have)
 Air Aspirating Foam Nozzle
 Articles
o Tips for Using Foam Eductors (attached)
o A Firefighter’s Guide to Foam (on-line)
Training Goal
For this month’s training, you will focus on foam for firefighting use using the in-line foam
eductor. The in-line foam eductor is a lost tool (lost in the compartment and never trained
on) and firefighters need to refresh on the use of it, as well as foam types available to
them, percentages to use foam and methods to apply it.
Training Objectives
1. Foam Review – Identify the various types of foam, the characteristics of each and
their uses, the equipment required to apply them and application techniques. (2-3
Hours)
a. How Foam Works/Generated
i. How Foam Extinguishes
ii. Foam Tetrahedron
b. Expansion Rates
i. Low Expansion
ii. Medium Expansion
iii. High Expansion
c. Types of Foam
i. Class A Foam
ii. Class B Foam
1. Protein Foam
4. AR-AFFF
2. AFFF
5. AR-FFFP
3. FFFP
iii. Polar Solvents vs. Hyrdocarbons
d. Foam Percentages
i. Class A – 0.1 to 1.0%
ii. Class B – 1 to 6%
e. How Foam is Injected
i. Portable Foam Proportioners (what we are covering)
ii. Apparatus-mounted Proportioners
1. Around the pump proportioners
2. Balanced pressure proportioners
3. Installed in-line eductors
iii. Compressed Air Foam Systems
f. How to Apply Foam
i. Techniques
1. Roll-On Method
2. Bank-Down Method
3. Rain Down Method
2. In-Line Foam Eductor – The in-line foam eductor is the simplest foam proportioning
system used in the fire service. It can flow all foam types and because of this its
versatility, compared to integrated systems, is unmatched. Utilizing your Firefighter
Skill Evaluation sheet, have each member assembly the in-line foam eductor so that
the eductor is set to the proper nozzle and foam concentrate, as well as pumped at
the proper pressures. In addition, ensure the firefighter: (2 Hours)
a. Understands how back-pressure affects the Venturi affect.
b. Understands the importance of flushing the in-line eductor and how to
do it.
c. How to improve the quality of finished foam through the use of nozzle
attachments (e.g. air aspirating nozzles).
d. Understands the most common reasons for failure to generate foam
(IFSTA Essential Pg. 746).
3. Applying Firefighting Foam - It is important to use the correct techniques when
applying foam from hand lines. If incorrect techniques are used, such as plunging
the foam into a liquid fuel, the effectiveness of the foam is reduced. Utilizing your
Firefighter Skill Evaluation sheet, have each member practice applying actual
finished foam, given a scenario, using the three (3) techniques: (1 Hour)
a. Roll-On Method
b. Bank-Down Method
c. Rain-Down Method
4. Minimum Company Standards – Review and re-practice the following MCS
evolutions, incorporating the above training objectives. Be sure to use the In-Line
Foam Eductor. (1 hour each).
 1 3/4" Pre-Connect Foam Attack
5. MCS Testing – Utilizing the MCS Individual Competencies Evaluation Form have
your deputy fire chief evaluate your crew on the 1 3/4" Pre-Connect Foam Attack.
And one (1) additional minute to the evolution to compensate for the assembly of
the in-line eductor. Retain a copy of the MCS for your record.
6. Firefighter Skill Evaluation (#2) – Utilizing the attached AzCFSE skill sheets, all
members shall be evaluated on the following skills. Note: All members may and
should be allowed to practice, but not before the evaluation.
 #142 – Assembling and Operating a Foam Fire Stream
 #141 – Correct Foam Selection
WMAF&R
Monthly Training Completion Form
By signing below I am stating that each member listed has completed the objectives listed
in the March 2012 WMAFR Monthly Training Packet (F
FIREFIGHTING FOAM). I am also
stating that each member is proficient at the individual skills and their appropriate
application. The following evolutions have been completed:
□
□
□
□
□
□
Foam Review
Inline Foam Eductor
Applying Firefighting Foam
MCS Practice: 1 3/4" Pre-connect Foam Attack
MCS Testing: 1 3/4" Pre-connect Foam Attack (+1 minute addition)
Firefighter Skill Evaluations: Assembling and Operating a Foam Fire Stream and
Correct Foam Selection
Each member is responsible for the information provided in this training packet. Members
will be individually evaluated on the skills included in this packet during the quarterly
evaluation/training session(s).
Officer’s Printed Name
Date
Officer’s Signature
Date
Members in attendance
Name
Foam
Review
In-Line
Foam
Eductor
Applying
FireFighting
Foam
MCS
MCS
Testing
Forward completed form to the Deputy Fire Chief for retention in the training file.
FF Skill
Eval. #3
Tips for Using Foam Eductors
By Keith Klassen
When asked if our apparatus has foam capability, most fire departments will respond in the
affirmative. For many departments, saying “yes” means that they have a foam eductor. Eductors
may be portable or plumbed into the apparatus. If they’re portable, they’re usually relegated to
the back of the engineer’s cabinet where they’re covered in a layer of dust. If they’re plumbed,
they’re often plugged with dried foam concentrate. Both situations are a good indication of how
infrequently we use them. This lack of use is often due in large part to a lack of training and
practice with the system. This month, we’ll shed some light on the mysteries of eductors.
How It Works
Foam eductors operate using the Venturi Principal. The eductor’s inlet has a large diameter as
compared to the small diameter in the center or Venturi area of the unit. The outlet of the
eductor returns to the original inlet diameter. The result is that all the water entering the eductor
is forced through the small center opening. In order for this to occur, the velocity of the water
must increase in small diameter. The increase in velocity reduces pressure in the Venturi area,
which allows the foam concentrate to enter the water stream as atmospheric pressure pushes
on the concentrate in the foam bucket or tank. This is the same principal by which carburetors
provide fuel to engines and airplane wings create lift.
Eductor Placement
Eductors come in various sizes, ranging typically from 60 gpm to 250 gpm, and can be attached
directly to the apparatus discharge. They may also be placed between two hose sections in the
discharge line. Moving the eductor down the hoseline may be required if a long line is being
pumped, as there are restrictions on how much hose can extend past the eductor. These
restrictions range from 150 to 300 feet depending on the eductor.
The eductor may also need to be moved away from the discharge if the discharge plumbing is
creating turbulence entering the eductor. Such turbulence can disrupt the operation of the
Venturi.
Pump Pressures & Percentages
Eductors are typically pumped with a 200-psi inlet pressure. This is due to the high friction loss,
roughly 30 percent, through the small Venturi area. The pick-up tube can be placed in a foam
bucket or attached to a foam tank supply.
For Class B operations, a large supply of concentrate will be needed due to the high
percentages required. The percentage can be adjusted to 0.5, 1.0, 3.0 or 6.0 percent; some
models have a 0.25 percent setting. Each setting is simply a specific orifice size that allows the
correct amount of concentrate to enter the water stream.
During & After the Operation
Flows during the operation must remain constant at the rated gallons per minute. This fact
makes the use of an eductor problematic for Class A foam firefighting where lines are constantly
being opened and closed. Eductors work much better in Class B operations where foam is being
flowed constantly on a fire or a spill for a longer period of time.
When the operation is complete, the eductor must be flushed. This is best done by removing the
pick-up tube from the concentrate source and placing it in a bucket of water. The hoseline can
then be flowed until clear water is exiting the nozzle. Important: Do not leave foam concentrate
in the eductor as it will dry, attract dirt and plug the small orifices. It may also cause the internal
check ball to stick. If the check ball is stuck open, this could result in water flowing back into the
concentrate supply. If the check ball is stuck shut, it could result in no foam entering the eductor.
Things to Remember
When using foam eductors, remember that they’re situation-sensitive. They must be operated in
precisely the correct parameters to operate effectively. For example, the flow through the
eductor must match its rating. Drastic variations and/or incorrect flow will affect the pressure
drop through the Venturi and, therefore, prevent its operation. The eductor must also be
matched to the correctly adjusted nozzle, which must discharge at a constant rate.
There are several other factors that will disrupt the eductor’s operation. These factors have one
thing in common: They all create 5 psi or greater of back pressure downstream of the eductor.
One factor, elevating the nozzle more than 10 feet, creates head pressure. Another factor,
excessive hose beyond the educator, increases friction loss. Other factors, such as an incorrect
or partially opened nozzle and kinks in the hoseline, restrict flow, creating back pressure.
Final Thoughts
Eductors can be great tools, but they must be set up and operated properly to be effective. As
with everything that we do in the fire service, training is the key. Regular practice with your
equipment will ensure that the steps for proper operation are second nature when the call
comes in at 0 dark 30.
A firefighter operates a foam
eductor. Remember: Eductors can
be great tools, but they must be set
up and operated properly to be
effective. Photo Keith Klassen
A selectable gallonage nozzle
must be adjusted to match the
eductor flow rating.
Download

(Firefighting Foam).