Each NBC-77 SOF gas mask filter is sealed in a plastic bag by the manufacturer. Store the filters unopened in a clean place at an even temperature, ideally at -5 to +30°C, with relative humidity below 80%. Sealed filters also tolerate conditions of -30 to +50°C and RH below 95%. The storage period (month and year) for filters is marked on the filter label. Do not try to regenerate the filters. Never clean the filters with compressed air or compressed water.

Store the drop-leg pouch in a dark, cool, and dust-free place that is ventilated regularly and without sudden temperature changes. Temperatures may vary between 10°C and 25°C, with relative humidity up to 65%. Stored products may not be exposed to radiant heat or sunshine. Fuels, solvents, lubricants, and other inflammable substances may not be stored with the masks, as well as any electric machines or appliances producing electric sparks or discharges during operation (ozone creation).

Avoid deformations of rubber parts of the facepiece and internal mask when storing. Inspect regularly to ensure effective sealing.

Potassium iodide tablets should be stored at 20-25°C (68-77°F), dry and with foil intact.

Standard MD-1 Children’s Gas Masks must be stored in a dark, cool, and dust-free environment that is ventilated regularly and free from sudden temperature changes. Temperatures may vary between 5°C and 25°C, with relative humidity up to 60%. The stored products should not be exposed to radiant heat or sunshine. Fuels, solvents, lubricants, and other inflammable substances must not be stored with the masks.

Do not store with or near any electrical machines or appliances that produce electric sparks or discharges during operation (ozone creation).

Avoid deformation of the rubber parts of the facepiece and internal mask when storing the masks. Inspect gas masks regularly to ensure they effectively seal to the user's face, as needed.

You would have to perform a negative pressure test. To do this, you would put the mask on your face, take a deep breath out, cover the inhalation valve (make sure the opposite side has the 40mm cap in place), and take a deep breath. If the mask sucks tight to your face without leaking air, you know that this mask fits. 

Filter use time depends on a few factors, including atmospheric conditions, contaminant type, concentration, along with your breathing rate. As a general rule of thumb, we would suggest having two filters per person per day for emergency evacuation purposes. If you'd like specific data on use time, you can look at the brochure that goes into breakthrough times along with the application.

Typically, it's never recommended to swap filters while you're in the thick of it. We are also selling escape filters, so the goal is for you to get out of the danger zone as fast as possible.

If you ever find yourself in a situation where you'll need to hot-swap filters while in the thick of it, you'll need to get proper training in order to execute the "Mask Clearing & Sealing" procedure safely. We suggest doing independent research on procedures of this level, as these are typically only taught in professional institutions.