Finding a respirator that fits

Finding a respirator that fits well is crucial for protection. Tight-fitting respirators, such as half and full face masks, create a seal with the wearer’s face. If the respirator does not fit properly, air can leak in through gaps around the mask instead of being drawn through the filters.

There is no ‘one size fits all’ approach to selecting a respirator. Each person’s face is a slightly different shape and size, and the mask must fit the wearer’s facial features to achieve an effective seal.

For over 50 years, the only available anthropometric information for respirator sizing was comprised of measurements taken in the US military during the 1950s and 1960s. This data was unrepresentative of the modern workforce, with measurements only being taken from predominantly male, military-age, physically healthy participants.

This meant that respirators only needed to fit wearers with similar facial features in order to pass testing, resulting in a large number of approved masks that did not fit many who needed to wear them for protection at work.

In 2003, Zhuang and Bradtmiller conducted a large anthropometric survey of the US workforce, collecting data for 18 facial dimensions plus height and weight from a sample of 3997 subjects covering a range of demographics.

The study included 2543 male participants and 1454 female participants, with ages ranging from 18 to 66 years, and included a range of racial/ethnic groups.

This research helped to inform a new international standard, ISO 16976-2, published in 2015. The ISO standard uses the results of this study supplemented with additional data for other countries to designate headforms for respirator sizing. Five headforms are designated in the standard: Small, Medium, Large, Short-Wide, and Long-Narrow.

The small, medium and large headforms are varying sizes with similar facial dimensions, whereas the Short-Wide and Long-Narrow headforms are based on different dimensions. A Short-Wide mask can enable a better fit than S or M masks for some half mask wearers.

The JSP Force?8 half mask is available in Small, Medium, Large, and Short-Wide sizes to enable an effective fit for a wide range of wearers.

Extensive research was carried out to assess the fit provided by the Force?8 mask across a range of face sizes and shapes. In two studies, the mask was assessed on 214 participants using Ambient Particle Counting (APC) quantitative fit testing methods.

The collected data was analysed and used to evaluate the fit provided by the Force?8 mask, directing product development to offer a secure face fit for more wearers.

The research also contributed to the expanded range of Force?8 respirators now available. New mask sizes, developed using the headforms designated in ISO 16976-2 along with JSP’s collected facial measurement data, provide a fit for a wider range of face sizes and shapes.

Adding Small (S) and Large (L) masks to the Force?8 range provided a choice for those who find a medium mask too large or too small to find a good fit. The latest Short-Wide (SW) mask offers an alternative fit for those who cannot achieve a fit with Small or Medium.

A size guide is available for use with the Force?8 mask. Request a size guide or contact [email protected] to find out more about the Force?8 half mask range.

Fit testing is required for all tight-fitting respirators. Learn more about fit testing. Looking for disposable respirators? Read the study on disposable mask fit here.