10 Jul 2018

Mask Standards have changed – AS 4381:2015

The ADA accreditation requirements have changed in regards to the single-use face masks standard (AS 4381:2015). In order to be accredited by the ADA, dental practitioners and their surgeries must be wearing level 2 masks. The standard divides masks into three levels (1, 2, 3). All levels have different purposes and are for different healthcare environments. In a nutshell: Level 1 is for general purpose medical procedures, level 2 is for use in dental environments, emergency departments and where minimal droplet exposure may occur, and level 3 is for all surgical procedures and major trauma (mainly in medical).


What is the difference between the old requirements to the new?

Besides introducing the three levels, the Standards committee has introduced a requirement that all masks need to meet a minimum fluid resistance level. A level 1 mask requires an 80mm Hg (millimeter of mercury – unit of pressure equal to 1 torr) resistance to penetration by synthetic blood (i.e. fluid resistance), level 2 requires 120mm Hg and level 3 160mm Hg. These measurements are given relative to the atmospheric pressure – we use the same measurements to measure blood pressure (which has an average of 120 mmHg). This purely measures the masks ability to minimize fluids from travelling through the material and coming in contact with the wearer – the higher fluid resistance, the better protection.

Particle Filtration Level (PFE) is not required anymore to meet the Australian (4381:2015) mask standards. This requirement has been placed into the Respirator Standard (AS NZS 1715). Masks in the Australian standard are measured on 3 performance metrics:

  1. Bacterial filtration efficiency (BFE)
  2. Differential Pressure (for measuring breathability)
  3. Splash resistance to blood and body fluids (R)


How can you identify the level of mask you are currently using?

The only way to identify which mask you are currently using is by checking the mask box or assuming the level from the thickness of the mask. Masks that are a higher level (2 and 3) will have a higher ply (i.e thickness) as they have a higher fluid resistance measure. It is recommended to ask the distributor who you have purchased the mask from, which level the mask is.

Therefore, to be accredited by the ADA a level 2 mask is required to be worn throughout the surgery. However, it is also recommended that by the standards, surgeries implement wearing and purchasing level 2 masks as they have a higher fluid resistance, breathability and overall greater protection for patients and staff.


Find out how to choose the right mask here 



Proud Leaders in Infection Control Since 1988


Recent Posts