NIOSH Approves First Elastomeric Half Mask Respirator Without Exhalation Valve
NIOSH has approved the first elastomeric half mask respirator (EHMR) without an exhalation valve, the agency announced via email on Nov. 16. The respirator, manufactured by MSA, is approved for use with either P95 or P100 particulate filters and can be used for both personal protection and source control. NIOSH notes that the particulate filters are available with an integrated splash guard to “improve the ease of completing a user seal check, to help protect from liquids, and to aid in wiping down the filter housing with disinfectant.”
EHMRs, tight-fitting respirators made of synthetic or rubber material, can be repeatedly disinfected, cleaned, and reused. The new device, the MSA Advantage 290 LS Respirator, covers the wearer’s nose and mouth and uses two filters, the company stated in a press release (PDF). The respirator was expected to be available for preorder in December 2020.
“There are many benefits of deploying a respiratory protection program that incorporates EHMRs, including cost-efficiency, reduced space requirements for PPE warehousing, and fewer concerns associated with PPE insecurities during a pandemic,” said Greg Martin, MSA vice president of Product Strategy and Development.
Elastomeric respirators are identified by CDC as alternative personal protective equipment during the COVID-19 pandemic in healthcare settings where N95 filtering facepiece respirators (FFRs) are unavailable or in short supply. But the pandemic has raised concerns that respirators with exhalation valves may allow unfiltered, exhaled air to escape into the environment, which would mean that they do not offer source control to protect others in case the wearer is infected with SARS-CoV-2. According to NIOSH, both the agency and manufacturers have been working to address these concerns—NIOSH by conducting research and manufacturers by working to produce an elastomeric respirator that addresses concerns related to exhalation valves.
The respirator, manufactured by MSA, is approved for use with either P95 or P100 particulate filters and can be used for both personal protection and source control.
A post to the NIOSH Science Blog dated Sept. 8, 2020, provides some advice for using EHMRs with exhalation valves as source control. The post suggests covering the exhalation valve with a surgical mask, procedure mask, or cloth mask, but doing so in such a way that does not compromise the respirator’s fit. The authors also state that NIOSH has undertaken studies to assess what is coming out of exhalation valves and ways to effectively cover the valves. According to CDC guidance, elastomeric respirators with exhalation valves should not be used in settings where a sterile field must be maintained, as in surgery.
The CDC guidance also presents suggestions for conservation of elastomeric respirators under conventional, contingency, and crisis circumstances. Conventional strategies should not be used during a pandemic, the agency says. Contingency strategies apply to emergency situations where each employee has exclusive use of an individual elastomeric respirator, while crisis strategies apply when supplies are too low to allow each healthcare worker to use a dedicated elastomeric respirator.
In a webinar held Nov. 18, Maryann D’Alessandro, director of the NIOSH National Personal Protective Technology Laboratory, said that many healthcare workers prefer elastomeric respirators to FFRs for reasons of comfort. But because healthcare workers are less familiar with elastomeric respirators, additional training may be necessary to ensure the devices are used properly.
See the NIOSH Certified Equipment List for more information on NIOSH-approved respirators. The new MSA device has NIOSH approval numbers TC-84A-9260, TC-84A-9261, TC-84A-9256, and TC-84A-9257.