Self Contained Breathing Apparatus

Transcription

1 Manchaca Fire / Rescue Probationary Firefighter Academy Self Contained Breathing Apparatus SFFMA Section 27: Self Contained Breathing Apparatus

2 SCBA Protective Qualities The SCBA is designed to protect the user for hazardous atmospheric conditions. Common hazards include:

3 IDLH Immediately Dangerous to Life or Health Firefighters perform their duties in a variety of conditions. Often, being exposed to our work environment can result in injury, illness, or death if proper PPE is not in use. SCBA is a vital tool for firefighter protection. SCBA should be worn whenever there is evidence of or the possibility of an IDLH atmosphere

4 Carbon Monoxide CO is one of the most abundant fire gasses we encounter. CO levels can be monitored by instruments that we carry on our apparatus. We use CO as a benchmark for safe atmospheric levels as CO levels drop due to fire extinguishment and fresh air ventilation, other toxic gasses will drop in concentration as well. Per MVFD policy, firefighters can operate without SCBA when CO levels are below 50 parts per million (ppm) This is the Short Term Exposure Limit or STEL (the safe level of exposure over an 8 hour work period). Typical fireground operations are much shorter in duration, resulting in an even lower exposure

5 Other Fire Gasses Asphyxiates Displace oxygen from the atmosphere or interferes with oxygen use at the cellular level Carbon Monoxide Hydrogen Cyanide HCN Carbon Dioxide CO2 Irritants Reacts with moisture in the respiratory track to form irritant (corrosive) compounds. Hydrogen Chloride HCl Phosgene COCl2 Nitrogen Dioxide NO2 Ammonia NH3 Chlorine Cl2

6 Requirements of the SCBA Wearer The additional weight, limited flexibility, narrowed field of vision, and foreign environment of the SCBA creates challenging work conditions. The wearer must be physically, medically, and mentally prepared.

7 Limitations of SCBA While the SCBA is a vital part of our protective ensemble, allowing us to go places we could not without it; it also adds limitations to the wearer and additional stresses. The SCBA is not a magic shield. It cannot protect you from hazards such as chemicals absorbed through the skin, excessive temperature exposures (beyond the design of the equipment), and over extending your air supply

8 SCBA Air Supply Limitations The times shown here are at best, estimates. All of the factors listed on the right will play a role in air supply durations. When multiple negative factors are in play, air supply times can be as low as 7-10 minutes.

9 Types of SCBA Open-circuit SCBA Commonly used in fire service Uses compressed air Exhaled air vented outside system Closed-circuit SCBA Rarely used in the fire service Uses compressed or liquid oxygen Exhaled air stays within the system for reuse MVFD uses Open Circuit SCBA

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12 SCBA Air Cylinder Sizes There are a variety of SCBA manufacturers as well as cylinder pressures and sizes. Higher pressures allow more air to be contained within a given space. SCBA cylinders can be found in these sizes: 30-minute, 2,216 psi, 45 ft3 cylinders 30-minute, 4,500 psi, 45 ft3 cylinders 45-minute, 3,000 psi, 66 ft3 cylinders 45-minute, 4,500 psi, 66 ft3 cylinders 60-minute, 4,500 psi, 87 ft3 cylinders MVFD uses 30 minute, Low Pressure (2216 psi ) cylinders

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15 Ways of Mounting / Storing SCBA Seat Mount (Engines/Rescue) Side Mount (on the exterior of the rig none in MVFD) Compartment Mount (Tenders / BT501 and 502) Stored in Case (Command / Battalion / Squad)

16 SCBA Safety Precautions Before using SCBA, follow department SOPs to obtain certification that you are physically fit. Closely monitor how you are feeling; rest when you become fatigued. Never remove or compromise your facepiece until you have left the contaminated area. Always work in groups of two or more.

17 SCBA & Emergencies Do not panic! Panic causes rapid breathing that uses more valuable air. Stop and think. How did you get to where you are? Downstairs? Upstairs? Use the portable radio to announce your last known location.

18 SCBA & Emergencies Listen. For noise from other personnel For hose and equipment operation For sounds that indicate location of the fire Activate your PASS device. Place a flashlight on the floor with the light shining toward the ceiling.

19 SCBA & Emergencies Lie flat on the floor close to a wall so that you will be easier to find if you are exhausted or feel you may lose consciousness. Use one of the following methods to find a way out: Follow the hoseline out if possible. Crawl in a straight line. Crawl in one direction once in contact with wall. Call for directions, call out, or make noise. Break a window or breach a wall to escape if possible.

20 Controlled Breathing Techniques These techniques will extend air time. It is important to utilize these techniques when trapped and having to await rescue.

21 Personal Alert Safety System (PASS) Mandated by NFPA 1500 Assists rescuers in locating a downed firefighter Sounds alarm when firefighter activates it manually or remains motionless for approximately 30 seconds Sounds a pre-alarm after seconds to help prevent false alarms (move the PASS to reset it before the full alarm mode activates) Once the PASS is in full alarm, it can only be reset by pressing the reset button on the side of the PASS (press the button twice)

22 PASS Use MVFD PASS devices will power-up automatically when the SCBA cylinder is turned on. When searching for a trapped firefighter, listen for the PASS by stopping in unison, controlling breathing. Turning your head slightly from side to side will sometimes help determine the direction of the sound Turn PASS device off to facilitate communication when downed firefighter is located.

23 PASS Use MVFD PASS devices also give a low air alarm when there is approximately 500 psi remaining. This alarm sounds different and utilizes yellow flashing LEDs It cannot be reset like the PASS alarm. No Alarms Manual PASS activation Low Air Alarm Reset button PASS Alarm

24 Wearing SCBA in areas of obscured visibility Crawl whenever possible to remain away from higher heat and allow you to feel around as you move along. Operate in teams of two or more Crews must always be oriented. (know where each other is located and at least one member must have contact with the path to the outside) Working off a wall Working off a hoseline Visual Contact Physical Contact Verbal Contact Rope line Extending with webbing or tool

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26 Monthly SCBA Inspection & Maintenance Check all components for deterioration. Ensure there are no leaks around valves and air cylinder connections. Check operation of all gauges, valves, regulator, exhalation valve, and low-air alarm.

27 Annual SCBA Inspection & Maintenance Requires the expertise of a factory certified technician Cylinders must be stamped or labeled with date of last hydrostatic test: Steel and aluminum Every five years Composite Every three to five years MVFD SCBAs are flow tested annually by a certified technician MVFD cylinders are either fiberglass composite or carbon fiber composite cylinders The cylinders are tested on a 3 year or 5 year basis. The test cycle is determined by a code number on the cylinder

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29 Recharging SCBA Cylinders There are four components to a cylinder recharging system Compressor Air Purification System Cascade System (air storage) Charging Station

30 The Compressor Compressors are usually three to four stages and electric powered. Electric is preferred because gas or diesel can contaminate the air used to fill the cylinders. The compressor can be stationary in a building or mounted in a vehicle. When air is being compressed it can heat to as much as 300 F. The compressor has cooling systems on it so that the air is only about 10 F to 25 F above the ambient air temp when it leaves the compressor to go to the cylinders

31 The Compressor The compressor intake should have a filter on it and be located as far from any source of contamination as possible. Vehicle exhaust Chimneys Fire extinguisher refill sites Piping should be noncorrosive. Galvanized pipe should not be used due to zinc deposits.

32 The Air Purification System The air passes through a series of filters that remove impurities such as dust, oil vapor from the compressor, excess moisture, and carbon monoxide. The air is tested on a quarterly basis against NFPA standards for SCBA breathing air purity.

33 The Cascade System Once compressed and filtered, the air is stored in a series of large cylinders. Individual SCBA cylinders are filled from this storage bank. This allows cylinders to be filler faster. The compressor is typically used to maintain the air in the storage cascade.

34 The Fill Station The fill station typically has valves that control compressor air flow to either the cascade or to the SCBA cylinders. The fill site also controls air flow from the cascade to the SCBA cylinders. Cylinders are placed in fragmentproof containers to protect the operator in the event of a SCBA cylinder failure. Any fragments from a failure would be directed straight up instead of laterally, toward the system operator

35 The Fill Station Cylinders should be filled in a slow and controlled manner to prevent overheating of the cylinder. As a gas is compressed it heats up. This increase in temperature can show an artificially high pressure on the cylinder gauge. A hot cylinder that shows full on the gauge may lose sever hundred psi of pressure once it cools down. Cylinders should not be filled faster than 500 psi/minute