There are several respiratory hazards involved in fire fighting due to HOTS, which are high temperatures, oxygen deficiency, toxic or poisonous gases, and smoke or suspended particles. In order to avoid injuries and to survive a rescue, you need to know how to operate a breathing apparatus. An open circuit set will pass expired breath to waste through an exhalation valve that comes with a face mask. It provides air, and its duration depends on the competence, fitness and mental state of the individual.

Parts of a Breathing Apparatus

There are different sizes, types and makes of a breathing apparatus. A typical BA has a cylinder, low pressure warning device, harness, pressure reduction valve, demand regulator, pressure gauge, head harness and face mask. The low-pressure warning device is designed to indicate when the cylinder has around ten minutes of air left. The remaining air is known to be a safety margin. The demand regulator controls the supply of air to whatever is required by the user during a rescue operation. One’s depth of breathing determines the rate of supply. The pressure gauge is connected to the cylinder through a high-pressure hose. It is made to indicate the pressure of the cylinder. Elements of a face mask include a full vision visor, exhalation valve, head harness, regulator, and a speech diaphragm.


Operating a Breathing Apparatus during an Emergency Situation

Before fire fighting operations, the fire fighter must do some checks to ensure that the breathing apparatus is in good working condition. You should place the BA on a clean surface. The first thing that you need to check is the cylinder and its band adjustment. Be sure to untangle all the harnesses, as well as the facemask adjustment straps.

You should also make sure that the cylinder hydrostatic test date is not due. You should depress the standby mode reset button and shut the constant flow valve. Then open the main cylinder valve and see to it that the cylinder pressure is above the minimum needed for rescue operational use.

Now close the cylinder valve and check the pressure. The gauge should not fall more than 10 bars over a minute. Check the operation of the constant flow valve by opening it to remove the pressure in the set. Once the pressure drops, check the pressure gauge and make sure that the low-pressure warning device is working at the right pressure.

You should test the Distress Signal Unit in all its modes. If you find any faults with the breathing apparatus, you should record it and report. If there are no faults then, it is fit for fire fighting duties.

There are four stages of operating a breathing apparatus during a rescue attempt. These are donning, starting up, closing down and doffing.


Donning is the phase where the individual puts the breathing apparatus on the back and do the preliminary checks.


Starting Up

During this phase, the facemask of the breathing apparatus is fitted. The final checks are made to ensure that the apparatus is working properly.

Closing Down

After the emergency operation, the breathing apparatus is set to standby mode and the facemask is removed.


Doffing is the process of removing the set from the back of the wearer and prepared to be cleaned and placed in its storage place so that it can be used again in the next fire fighting operation.

What we do

Diamond Protection Pty Ltd (Diamond) is a leading provider of security, emergency and training services. Established in 1995, this Australian owned and operated company is committed to leading the way – to be the standard of excellence. Diamond operates an internationally certified Integrated Management System (IMS) incorporating ISO accreditation for Quality (ISO 9001:2008), Occupational Health & Safety (AS/NZS 4801 & OHSAS18001:2007) and Environmental Management (ISO 14001:2004) Systems. The company has placed significant importance in continual improvement and commitment to the community and environment.

Diamond works closely with clients throughout Australia and beyond to provide security audits, security guards / officers, patrols, risk management, emergency service officers, safety officers, life support and nationally recognised training courses in industrial skills, emergency (fire & rescue) and safety.

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