Chapter 7 Self-Contained Breathing Apparatus. Introduction Failure to use the SCBA properly can result in injury or death Respiratory system extremely.

Chapter 7

Self-Contained Breathing Apparatus

Introduction• Failure to use the SCBA properly

can result in injury or death• Respiratory system extremely

vulnerable• Fire departments must have a mask

rule• Wear and use SCBA in IDLH

atmosphere• SCBA necessary even during

exterior defensive operations7.2

7.3

Figure 7-1 Large volumes of smoke require the use of SCBA, even for exterior operations as shown here at a tire storage facility.

Introduction (cont’d.)• Any inhaled toxic gas can directly

cause disease of the lung tissue• One in 12 firefighters is injured in

the line of duty each year• Smoke inhalation accounts for 18

percent of fatalities– 21 percent of fireground injuries

7.4

7.5

Figure 7-2 These firefighters in full protective equipment, including SCBA, are ready to begin interior firefighting operations.

Conditions RequiringRespiratory Protection

• Oxygen deficiency• High temperatures• Smoke or by-products of

combustion• Toxic environments

7.6

Oxygen-DeficientEnvironments

• Fire consumes oxygen– Produces toxic gases– Displace or dilute oxygen

• Oxygen concentrations below 19.5 percent are oxygen-deficient atmospheres

• Affects on the human body:– Muscular impairment– Mental confusion– Death

7.7

7.8

Table 7-1 Effects of Hypoxia (Reduced Oxygen)

Elevated Temperatures• Respiratory system sensitive to

temperature• Air temperatures as low as 165°F can

cause death within 1 minute• Inhaling gases causes:

– Pulmonary edema– Asphyxiation– Long-term damage

• Temperatures in structure fire reach 1000°F– One unprotected breath will cause death or

severe damage to respiratory system

7.9

Smoke• Unburned products of combustion,

particles of carbon, tar, associated gases• Large amounts of gases due to use of

plastics• Inhalation of small amounts may be fatal• Four causes of damage by smoke:

– Asphyxiation– Chemical irritation– Chemical asphyxiation– Any combination of these

7.10

Effects of Toxic Gasesand Toxic Environments

• Combustion produces toxic gases and irritants– Affect short- and long-term health

• When combustion products combine may form lethal toxins

• Some common gases affect circulatory system

• Commercial occupancies may produce additional toxins– Requires higher level of protection

7.11

7.12

Table 7-2 Toxic Gases Formed as Products of Combustion

Carbon Monoxide• Produced in great quantity during

combustion process: one of most lethal gases found in a fire

• Colorless and odorless, always present• Found in homes with defective furnaces,

clogged chimneys• CO attaches to red blood cells and

prevents oxygen from bonding with hemoglobin

• Effects are compounded through repeated exposure

7.13

7.14

Table 7-3 Symptoms of Carbon Monoxide Poisoning

Hydrogen Cyanide• Colorless and produced by combustion of

natural materials as well as synthetics• Can be present long before ignition

temperature of material is reached– Off-gassing or quantitative decomposition

• Difficult to detect in the body – Very short half-life

• Significantly compounded when combined with carbon monoxide

7.15

7.16

Figure 7-5 The light smoke condition present during overhaul will contain large amounts of carbon monoxide and hydrogen cyanide, requiring SCBA protection.

Legal Requirements forSelf-Contained Breathing

Apparatus Use• Common sense: use SCBA on

every fire scene– Start to finish

• Regulations developed for SCBA use

• Organizations established regulations and standards

7.17

Title 29 Code of Federal Regulations, Section 1910.134

• Establishes standards for all entries into IDLH atmospheres

• April 1998 revision contains requirements related to interior structural firefighting– Defines interior structural firefighting as IDLH

• Requires the use of SCBA• Requirements for complete respiratory

protection program– Regular medical evaluation

7.18

NFPA 1500: Standard on Fire Department Occupational Safety

and Health Program

• Authority having jurisdiction (AHJ) must adopt the standard for the fire department

• Three additional standards:– NFPA 1404: minimum requirements for

protection programs– NFPA 1981: design and performance criteria– NFPA 1982: standards on PASS

7.19

Limitations of Self-Contained Breathing Apparatus

• Understand limitations to use unit effectively and safely

• Limitations of the SCBA unit itself– Size, weight, air supply

• Physiological limitations of the user

7.20

7.21

Figure 7-7 Continuous training with SCBA is one of the keys to effective firefighting operations.

SCBA Design and Size• SCBA units ad weight and bulk to PPE• SCBA cylinder consumed more quickly

than length of time rated for:– Limits advance into building– More frequent crew rotations

• Other concerns:– Restricted visibility– Added weight and bulk– Firefighter’s voice muffled– Limited air quantity

7.22

Limitations of the SCBA User• Physical, mental, emotional state

cause usage problems– Physical limitations: added weight and

bulk– Physiological limitations

• Lack of confidence in SCBA unit

• Physical stress and anxiety

• Emotional conditions

7.23

Air Supply Management• Air supply management

– Must understand air consumption rates– Individual point of no return– Heads up display– 10-10-10 rule

• Various methods of breathing take experimentation on the part of the firefighter– Use normal breaths and exhale slowly– Never hold breath– Controlled breathing is most efficient use of air

7.24

7.25

Figure 7-11 An example of an air consumption test.

Types of Self-ContainedBreathing Apparatus

• Two types of SCBA:– Open-circuit SCBA

• Exhaled air is vented to outside atmosphere

• Most common– Closed-circuit SCBA

• Exhaled air stays in the system for filtering, cleaning, circulation

• Sometimes used for specialized rescue incidents

7.26

Open-Circuit Self-Contained Breathing Apparatus

• Designed and built in accordance with NIOSH and NFPA standards

• Four basic assembly components:– Backpack and harness– Cylinder– Regulator– Face piece assembly

7.27

7.28

Figure 7-13 The four components of the open-circuit SCBA are the backpack/harness, cylinder, regulator, and face piece assemblies.

Closed-Circuit Self-Contained Breathing Apparatus

• Not used for firefighting operations• Most common use: hazardous materials

incidents• Air supplies range from 30 minutes to four

hours• Contain cylinder, filter system, regulator,

and valves• Clean and filter exhaled breath and add

oxygen– Air supply duration based on filtering/cleaning

and oxygen capacity of unit7.29

Open-Circuit SuppliedAir Respirators

• Open-circuit supplied air respirators (SARs)– Also called airline respirators– Remote air supply

• Commonly used for hazardous materials incidents– Confined space rescues

• Long-duration of air supply, mobility, agility

• SCBA escape unit with 510 minutes7.30

Donning and Doffing Self-Contained Breathing Apparatus

• Most common donning procedures:– Seat-mounted position in the apparatus– Side compartment on the apparatus– Storage case

• Refer to manufacturer’s instructions

7.31

General Considerations• Operational safety checks must be

performed• Conducted on a daily or regular

basis– Immediately prior to using the SCBA

unit

• If any component does not operate properly or is damaged, unit taken out of service immediately

7.32

7.33

Figure 7-23 Firefighters must perform regular checks of SCBA to ensure the unit’s ability to operate.

Storage Case• Two methods to don unit:

– “Over the head”– “Coat”– Choice is a matter of personal

preference and training

• Refer to donning instructions for the particular SCBA unit

7.34

Seat-Mounted Apparatus• Allows for quick donning• Unit readily available for regular

inspection• Three important safety requirements:

– Storing of the face piece– Donning the unit while vehicle is moving– Checking the cylinder gauge

• Never don while vehicle is in motion• Check gauge before response or use the

buddy system

7.35

Compartment or Side-Mounted Apparatus

• Similar to seat-mounted position except firefighter is standing

• If mount bracket wrong height, use “coat” method

• Follow donning methods for particular mounting style

7.36

Donning the SCBA Face Piece• Most SCBA face pieces donned in a similar

manner– Difference in style of head straps, regulator

location

• Essential to protect firefighter from toxic gases

• Firefighter must be fitted for the face piece to be used with a particular manufacturer’s SCBA

• Prohibit anything that may interfere with proper fit and seal of face piece– Examples: eye glasses, beards, sideburns

7.37

Removing/Doffing theSCBA Unit

• Generally to remove SCBA donning procedure is reversed

• If awaiting another assignment, remove face piece– Allow normal breathing, conserve air

• Do not wear the mask without air flowing into it

• Regulator or face piece must not be contaminated

• After assignment complete, report to rehabilitation 7.38

Self-Contained Breathing Apparatus Operation and Emergency Procedures

• Fire departments must establish respiratory protection programs

• Firefighters must be proficient in the safe use of SCBA– Donning and doffing procedures– Individual limitations– Limitations of SCBA unit

7.39

Safe Use of SCBA• Essential to firefighter survival• SCBA unit and protective

equipment add weight and bulk– Increased exertion and loss of body

fluids

• Firefighters must be aware of symptoms of heat stress– Be aware of own limitations and

abilities

7.40

Operating in a Hostile Environment

• General rules:– Check in with accountability officer when

entering or exiting– Remain low, check the environment and

conditions– Never remove the face piece, maintain an

awareness of location– Ventilate as you advance if it does not spread

fire– Check for outside openings– Maintain direct contact with other team

members– Never enter a hostile environment alone

7.41

Restricted Openings• Probe tight spot with a tool• Be sure conditions on other side of

obstacle are safe• Shift pack to left side• “Swim” through obstacle backwards• “Forward dive” technique• Do not remove SCBA unless

absolutely necessary

7.42

7.43

Figure 7-31 Firefighters may have to get beneath an obstacle to facilitate their escape, which may also require them to lower their profile.

Emergency Procedures• Emergency procedures exist to assist a

firefighter in safe escape from hazard• Remain calm, rely on training and

knowledge• Never remove the face piece of the SCBA• Standard emergency check procedure

stressed• If entangled, do not pull forward

– Use wire cutters to cut one wire at a time– “Swim” method

7.44

7.45

Figure 7-32 Emergency procedures check.

Inspection and Maintenance of Self-Contained Breathing

Apparatus• Inspection on daily or regular basis• Always follow manufacturer’s

instructions• Procedures in this chapter may differ

from the recommendation

7.46

Daily Maintenance• SCBA units should be checked

daily• If used during emergency scene or

training exercise should be serviced in same manner

• Follow 10-step inspection procedure

7.47

Monthly Maintenance• Monthly SCBA check contains all

elements of the daily check– Adds several checks of mechanics of

system

• Irregularities noted and repaired or pull SCBA from service

7.48

Annual and Biannual Maintenance

• NIOSH and SCBA manufacturers require different functional tests of SCBA units

• Only manufacturer’s authorized or trained service personnel shall conduct these tests

• Firefighters should refer to the instructions for the SCBA units used

7.49

Changing SCBA Cylinders• Cylinders changed after use,

following local SOPs• Cylinder 90 percent full could mean

loss of 25 minutes of air supply– Could make the difference in successful

exit

• Follow 12-step replacement procedure

• Additional steps for two-person SCBA cylinder replacement

7.50

Servicing SCBA Cylinders• Cylinder serviced when below full

– Air source must be tested and certified– All cylinders must have a current

hydrostatic test date– All fill stations must have fragmentation

containment devices– All manufacturer’s recommendations

should be followed– Fill rate may vary

• Cascade system• Compressor/purifier system

7.51

7.52

Figure 7-36 (A) A cascade system is one of the systems available to service SCBA cylinders. These may be fixed or mobile units. (B)

(A) (B)

Lessons Learned• SCBA unit is to a firefighter as a weapon is

to a soldier• No substitute for proper SCBA training

– Continued practice and advanced training necessary

• Prevent failures: thoroughly inspect and test SCBA function as often as possible

• Firefighters must be prepared to go in harm’s way– Be knowledgeable and proficient in use of SCBA

7.53