Self-Contained Breathing Apparatus Chapter 7 Self-Contained Breathing Apparatus

Introduction Failure to use the SCBA properly can result in injury or death. Respiratory systems are extremely vulnerable. Fire departments must have a mask rule. Wear and use SCBA in IDLH atmosphere. SCBA is necessary even during exterior defensive operations.

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

Introduction (cont.) 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

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

Oxygen-Deficient Environments Fire consumes oxygen. Produces toxic gases Displaces or dilutes oxygen Oxygen concentrations below 19.5 percent are oxygen-deficient atmospheres. Affects the human body Muscular impairment Mental confusion Death

Effects of Hypoxia (Reduced Oxygen)

Elevated Temperatures Respiratory system sensitive to temperature Air temperatures as low as 74°C (165°F) can cause death within one minute Inhaling gases causes: Pulmonary edema Asphyxiation Long-term damage Temperatures in structure fire reach 540° to 1,300°C (1,000° to 2,400°F).

Smoke Unburned products of combustion, particles of carbon, tar, associated gases 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 Gases and Toxic Environments Combustion produces toxic gases and irritants. When combustion products combine, they may form lethal toxins. Commercial occupancies require higher level of protection. Some gases affect circulatory system. Carbon monoxide Hydrogen cyanide

Toxic Gases Formed as Products of Combustion

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

Legal Requirements for SCBA Use Common sense Regulations for SCBA use CSA Z 94.4-02 6.3.2.4.2 IDLH Atmospheres 6.3.2.4.3 Escape from IDLH Atmospheres NFPA 1500 Workplace Safety & Health

Limitations of SCBA Apparatus Understand limitations Limitations of the SCBA unit itself Size Weight Air supply Physical limitations Psychological limitations

SCBA Design and Size SCBA units add 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 Psychological limitations Lack of confidence in SCBA unit Physical stress and anxiety Emotional conditions

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

Air Supply Management Air supply management Understand air consumption rates Point of no return Heads up display 10-10-10 rule Various methods of breathing Use normal breaths and exhale slowly. Never hold breath. Controlled breathing is most efficient use of air.

An example of an air consumption test.

Types of Self-Contained Breathing 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

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

Donning and Doffing Self-Contained Breathing Apparatus Most common donning procedures: Seat-mounted position in the apparatus Side compartment on the apparatus Storage case Over the head method Coat method 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.

Donning the SCBA Face Piece 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 the SCBA 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 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. Heat stress Individual limitations and abilities

Operating in a Hostile Environment General rules: Check in 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.

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

Emergency procedures check.

Inspection and Maintenance of SCBA Inspection on daily or regular basis Always follow manufacturer’s instructions. SCBA units should be checked daily. Follow step inspection procedure. SCBA should also be checked following an emergency scene or training. Monthly SCBA check contains all elements of the daily check. Irregularities noted and repaired or pull SCBA from service.

Annual and Biannual Maintenance Functional tests Only manufacturer’s authorized or trained service personnel shall conduct these tests. Firefighters should refer to the instructions for the SCBA units.

Changing SCBA Cylinders Cylinders changed after use Cylinder 90 percent full could mean loss of 25 minutes of air supply Follow 12-step replacement procedure. Additional steps for two-person SCBA cylinder replacement

Servicing SCBA Cylinders Cylinder service Air source must be tested and certified. Hydrostatic test date Fragmentation containment devices All manufacturers’ recommendations should be followed. Fill rates vary. Cascade system Compressor/purifier system

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

Lessons Learned SCBA unit is to a firefighter as a weapon is to a soldier. No substitute for proper SCBA training Prevent failures. Firefighters must be prepared to go in harm’s way. Be knowledgeable and proficient in use of SCBA.