Unlike most reusable respirators, it's relatively easy to hear someone talking that's wearing the Envo mask. The Envo mask has an exhalation valve. The company ships each mask with a valve plug which can be used to seal the exhalation valve. A filter cover that lacks an exhalation valve is available as an optional accessory.
The Envo mask is made by Sleepnet Corporation, a company that had been manufacturing masks for sleep apnea. The envo mask received its first NIOSH certification in September of 2019. According to a news article, founder Tom Moulton got the idea to create the Envo mask after working a demolition project and becoming frustrated with the poor quality of most disposable masks:
“There’s got to be a better way,” Moulton thought to himself. He started working with his Sleepnet engineers to create what he thought might be a construction-type mask using his AIRgel.. -Interview with Sleepnet founder
Pros and Cons
The big advantage of the Envo mask is the gel cushion seal. Many people find it very comfortable. However, it doesn't fit everyone and the head harness and neck strap being one continuous loop does not allow independent adjustment -- allowing fit to fluctuate during wear. Fit testing is important.
The downside, from a cost perspective is not only the upfront cost of the facepiece, which is about double that of standard elastomeric respirators, but that the manufacturer recommends replacing the filter after every 8 hours of use at over $2/filter. Thus, the total cost of ownership is actually greater than for filtering facepiece disposable N95s, if you follow those directions. By contrast the cartridges for an elastomeric respirator (e.g., MSA Advantage 290 respirator, a NIOSH approved N95 without exhalation valve) can be used for up to a year or more without replacement in an environment that has low levels of particulate air pollution (e.g., healthcare) -- making total cost of ownership orders of magnitude less than for the Envo mask.
Some videos about the Envo mask:
- ENVO MASK | ER NURSE REVIEW | 7 months later - on YouTube
- A physician's review of the Envo mask (and other masks), at 7:57
- Another physican's review of the Envo mask (ear strap version)
- Performing a qualitative fit test in an Envo mask
- "'I’ve learned more from my failures': Tom Moulton of Sleepnet is Entrepreneur of the Year" - Jun 2021 news article describing the history of the Sleepnet Company and the Envo mask.
- "Why Sleepnet of Hampton's N95 mask is getting national attention" - Nov. 2020 news article on the Sleepnet company's pivot from sleep apnea masks to the Envo mask.
- "New Face Masks Relieve Pressure on N95 Supplies" - Wall Street Journal article from Nov. 2020 that mentions the Envo mask
- "Hampton company ramps up production of reusable N95 masks" - April 2020 article and video on the Sleepnet company's pivot to making N95 masks.
- Envo mask official website, where the respirator can be purchased.
- Website featuring reviews of the Envo mask as well as other consumer-oriented reusable N95 respirators.
- Envo mask test results - provided by the company.
- Short review of the Envo mask and other reusable / elastomeric respirators on PatientKnowHow.com
- An independent qualitative aerosol test of the Envo mask N95 filters.
- List of other respirators with Encycla pages