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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
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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 operations
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
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
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
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
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
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
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
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
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 BreathingApparatus Use • Common sense: use SCBA on every fire scene • Start to finish • Regulations developed for SCBA use • Organizations established regulations and standards
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
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
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
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
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
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
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
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
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 unit
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 minutes
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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