Back in April, we told you that you probably shouldn’t decontaminate disposable N95 respirators in your home oven, but we also showed you how to do it if you were determined. Now, though, the United States Department of Homeland Security is recommending a way to decontaminate those masks at home in a programmable pressure cooker with a sous-vide setting, like the Instant Pot Duo Evo Plus. This method lets you reuse a disposable respirator up to five times.
(So if you bought yourself a multi-cooker when we recommended sous-vide-ing meat during the pandemic, you can pat yourself on the back now.)
Why the multi-cooker method works
First of all, N95 masks are marked as single use for a reason. But throughout the coronavirus pandemic, essential workers have felt N95 shortages. So the Instant Pot decontamination method is one you should use only when you’re desperate—not all the time for fun.
In fact, the DHS FAQ reads, “The only time one should consider decontaminating them for reuse is in critical supply shortage situations where there is a need for respiratory protection and mask supplies are not sufficient to provide protection to those who need it.”
The multi-cooker method works by quickly heating and holding masks at 149 °F (65 °C) for 30 minutes. The moist heat is what works for decontamination, and a paper bag is essential for this method. You put your N95s in a paper bag so some steam can get through and disinfect without ruining the mask with too much moisture.
This method should work for most N95s, but it isn’t approved for other types of masks. And it’s also worth noting that this method hasn’t been approved by the FDA.
Use an Instant Pot for mask decontamination
Here’s what you need to decontaminate your masks at home:
- An Instant Pot Duo Evo Plus or other programmable pressure cooker with a sous vide feature.
- A rack for the cooker, which should have been included in the box.
- Small binder clips, for raising the rack to the appropriate level.
- Distilled, bottled, or filtered water.
- Paper bags small enough to fit in the cooker.
- Staples or paper clips to close the bag.
- Disposable gloves
The process itself is pretty simple, and you can decontaminate up to three masks each time:
- Pour a half inch of water into the bottom of the pot.
- Place the rack in the pot, just high enough to keep the paper bag out of the water. If you need to raise the rack, attach the small binder clips to the bottom to act as “legs.”
- Place up to three nested masks in the paper bag. Homeland Security recommends wearing gloves while doing this and handling the masks with only one hand.
- Dispose of your gloves and wash your hands.
- Roll up the top of the bag and close it up with the staple or paperclip.
- Place the bag on the rack inside the cooker and secure the lid.
- Set the sous vide function for 149 °F (65 °C) for 30 minutes.
- Start the cook cycle.
Once the cycle is complete, remove the bag (the cooker should not be pressurized), remove the masks, and set them in a clean place to dry for one hour.
When the mask is dry, inspect it for any damage. If the mask is in good shape, it’s ready to wear again!