How to choose your respiratory protection?

Source: ED 6160 “Les appareils respiratoires” (respiratory equipment), published by INRS in July 2017

Filtering or powered ventilation masks, self-contained breathing apparatus, evacuation equipment, self-rescuers... All are respiratory protection devices ! The question is, when should you use them, and above all, how do you choose the right device to protect yourself?

Here's a guide to best practice when choosing your respiratory protection.

When should you use respiratory protection ?

Before introducing respiratory protection, it is essential to implement other preventive solutions, such as substitution of hazardous products or air purification techniques (process enclosure, pollutant capture, ventilation, etc.). If these measures are not possible, or if they are not sufficient, then respiratory protection must be provided.

Respiratory protective equipment is used :

  • when there is a risk of damage to health through inhalation of air polluted by gases, vapors, dust, aerosols or oxygen-depleted air in the workplace.
  • when responding to fires, gas leaks or enclosed spaces where the atmosphere could become hazardous by inhalation.
  • in enclosed spaces where the oxygen content tends to become rarer (contaminated zone).

There are many different types of respirator to suit every situation and every field. They create a physical barrier between the polluted atmosphere of the work area and the worker's face (respiratory tract, eyes, skin). These are Personal Protective Equipment (PPE), so you need to make the right choice to be well protected.

Conduct a workstation survey

You need to define the conditions of use beforehand:

  • The oxygen
  • Nature of pollutants (gas, vapour, dust, etc.)
  • Pollutant toxicity
  • Predicted worst-case concentrations of each pollutant in the air
  • Concentration limits in the workplace, if any (VLEP)
  • Particle size in the case of aerosols
  • The user's physical activity
  • Length of work to be performed
  • Other associated risks (liquid splashes, fire, etc.)

Respiratory equipment selection guide

There are two broad categories of respiratory protective equipment:

Self-contained breathing apparatus

  • The equipment supplies breathable air from an external source. The user is not dependent on the ambient air
  • Can be used in closed and confined spaces
  • Always use this type of protection if there is any doubt about the quality of the air, and in all atmospheres with an oxygen level <17%

Filtering respirators

  • The equipment filters and purifies the contaminated air. The user breathes the ambient air.
  • The ambient air must contain between 17 and 21% oxygen

To help you determine the type of respiratory protective equipment best suited to your needs, we have provided a decision-making chart based on the following questions:

  • When is respiratory protection used ?
  • What is the oxygen content during working hours ? NB: a normal oxygen level is between 17 and 21%.
  • What is the nature and toxicity of the pollutant ?
  • What is the pollutant's TLV or permissible concentration limit ?
Respiratory equipment selection guide
Class of filter efficiency for filtering respirators (gas masks)

Determine the level of protection

Once the family of devices has been selected (filtering or assisted ventilation masks, insulating devices, evacuation or survival devices), the minimum Protection Factor (PF) required must be defined.

Minimum Protection Factor required = Concentration of contaminant outside the facepiece / Permissible concentration of contaminant inside the facepiece or VLEP

For good protection, the Nominal Protection Factor (NPF) and the Assigned Protection Factor (APF) must be higher than the minimum required Protection Factor (PF).

For example: to choose an anti-gas filtering device, look for the most suitable device according to the protection levels shown in the table, and select the appropriate filter (type and class).

For example: to choose an anti-gas filtering device, look for the most suitable device according to the protection levels shown in the table, and select the appropriate filter (type and class).

did-you-know-be-atex

Did you know ?

  • For protection against carbon monoxide (CO), the use of self-contained breathing apparatus is recommended.
  • A full-face mask with a self-contained compressed-air device with a positive-pressure demand valve is required for insulating devices used for very high pollutant concentrations or when the oxygen content is lower than normal.

Adapting to the work situation

Once the family of respiratory protective equipment has been defined, the equipment must be adapted to the work situation. It is essential to involve future users in the selection process, as they will be able to describe their activity as precisely as possible.

The following parameters need to be taken into account:

  • Physical characteristics of the wearer (beard, face scars, etc.) that will determine the size and type of protection (helmet, hood, facepiece, etc.)
  • Whether the person wears glasses or contact lenses, because there are special devices for attaching glasses
  • Work patterns: air line breathing systems are better suited to more intense work; powered respirators can be used if the flow is sufficient to offset the negative pressure
  • The length of time for which the equipment will be worn: it is better to choose powered filtering respirators if you need to wear them for more than 1 hour
  • Visibility requirements: depending on the needs, we may recommend panoramic facepieces for improved visibility, single-use visors or hoods with a replaceable visor offering eye protection in case of projections
  • Communication requirements: there are models with phonic membranes and voice amplifiers enabling communication in harsh conditions such as confined spaces
  • Other personal protective equipment and accessories to be used: some types of equipment have integrated head, eye, ear and respiratory tract protection – they are useful for welding operations, for example.
  • Decontamination requirements applicable to  respiratory protective equipment
  • Thermal constraints

Fit testing

Respirator fit tests are recommended to help you choose the right size and model for each wearer,  and to make sure the seal between the facepiece and the face is as airtight as possible.

>> To find out more, please read through document ED 6273 published by INRS. <<

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