When selecting a respirator it is important to consider suitability for the task and wearer. Depending on the type or duration of work, certain styles of RPE may be more suitable than others. Wearer factors – such as health conditions, facial hair, face shapes – can determine the use of a particular type of respirator.
Understanding the differences between tight-fitting and loose-fitting RPE will help to determine which style is suitable in specific situations.
What is tight-fitting RPE?
Tight-fitting respirators create a tight seal with the wearer’s face to prevent external contaminants leaking inside the mask. Disposable respirators, reusable half masks and full face masks are all examples of tight-fitting RPE.
Negative pressure respirators – that rely on the wearer’s inhalation to draw air through the filters – must be tight-fitting. Powered air positive pressure respirators and breathing apparatus including airline / air-fed may be tight-fitting or loose-fitting.
What is loose-fitting RPE?
Loose-fitting respirators must be powered devices. The power unit maintains an atmosphere of positive pressure within the respirator headtop, preventing inward leakage without the need for a tight seal.
These respirators incorporate a hood, helmet or faceshield headtop, with a belt or head mounted power unit.
Fit testing
Fit testing is required for all tight-fitting RPE. As the mask requires a tight seal to provide protection, testing must be carried out to ensure the wearer can achieve a good respirator fit.
Tight-fitting powered air respirators must be fit tested with the power unit switched off, the respirator is adapted by the Fit Test assessor to make sure the wearer remains protected should the power unit fail. In this instance (powered unit failure) the respirator is only intended to provide short-term protection. If powered unit failure is experienced the wearer should leave the hazard zone immediately.
Learn how fit testing is conducted.
In addition to the initial fit test, wearers of tight-fitting RPE must perform a ‘fit check’ each time they put their respirator on.
Facial hair
Facial hair can compromise the seal of a tight-fitting respirator. Wearers are required to be clean-shaven to wear a tight-fitting facepiece. Even a small amount of facial hair or stubble interfering with the face seal can affect the respirators performance. Watch how facial hair affects fit test results.
Loose-fitting respirators provide a suitable option for those with facial hair. Loose-fitting respirators do not create a tight seal with the face, they are safe for use with stubble, moustaches and beards. Loose-fitting respirators will have limitations upon facial hair, neatly trimmed, well-groomed beards should NOT be exceeded. Seek advice from your RPE manufacturer.
Find out more about facial hair and loose-fitting RPE.
Compatibility
The selected respirator must be compatible with other PPE and other equipment, such as prescription (Rx) eyewear.
For tight-fitting RPE, compatibility is assessed via fit testing. The test subject is required to wear all other above the neck PPE along with prescription eyewear (if applicable) during the fit test. This ensures the respirator can provide an effective fit with all the other PPE worn.
Loose-fitting RPE can offer greater compatibility by combining multiple pieces of PPE into one. Helmet and faceshield headtops are available, providing multiple forms of protection. These types of headtops also allow prescription glasses to be worn comfortably underneath.
Medical conditions
Crucially, respirators must be suitable for each individual wearer. Some pre-existing medical conditions, such as breathing disorders and heart conditions, may prevent workers from being able to wear RPE or require them to wear certain styles.
HSG53 provides more information about medical conditions.
Wear time
Another consideration when selecting tight-fitting or loose-fitting RPE is wear time. Recommended continuous wear time for tight-fitting (non-powered) RPE is less than one hour. After that, the wearer should take a short rest period.
Loose-fitting RPE offers a better option for longer wear times. The power unit relieves breathing effort, allowing wearers to work for longer reducing fatigue. Airflow inside the headtop also helps to keep the wearer more comfortable.
Suitable wear times for each type of respirator are included in HSG53.
Work rate
Work rate refers to how much effort or energy is expended when carrying out a work task. At higher work rates, the wearer may breathe more heavily and sweat more which has the potential to affect RPE performance. Higher breathing rates can unsettle the respirator allowing contaminants to leak in. Sweating may cause the respirator to move around on the face, compromising the seal.
See HSG53 for more information on work rates and suitable respirators.
To select a suitable respirator, think about the individual wearer and tasks they will be carrying out. RPE needs to fit well and remain comfortable throughout use to keep wearers safe and protected. Consider any medical conditions, facial hair or compromising factors that could influence RPE loss of confidence in specific tasks.
Certain styles of respirators may be legally required for specific tasks or hazards. A full hazard risk assessment is needed to ensure the chosen respirator style provides adequate protection.
Learn more about loose-fitting respirators.
Find out how to select the correct RPE.
If you need further support, please contact our Technical Support Team using the email: technical@jspsafety.com or contact us via WhatsApp.