M17 gas mask

The M17 Protective Mask is a series of gas masks that were designed and produced in 1959 (as a replacement of the M-9 gas mask) to provide protection from all types of known chemical and biological agents present. The M-17 was issued to troops in the Vietnam war, and was standard issue for the U.S Army until it was replaced by the M-40 in the late 1980s and early 1990s. The mask has different components including a filter, a face piece and outserts. Filter elements in the face piece prevent harmful agents from entering the mask. The M17 series includes three types of masks, the M17, M17A1 and M17A2. An experimental transparent-silicone model was designed in 1966, but was turned down. Many countries have copied the M-17 design. Notable copies include the Bulgarian PDE-1, the Polish Mp-4, and the Czech M-10.

These protective masks have inbuilt systems that facilitate communication, a tube for drinking water (A1 & A2), and a pair of outserts to protect eye lenses and prevent fogging. The mask is packed in a carrier that also contains other items like a nerve agent antidote kit (NAAK) and a convulsive antidote for nerve agents (CANA). It also contains a waterproof bag to protect filter elements from water damage. Other components attached are mask hoods to protect the head and neck area, a winterization kit to prevent frost accumulation during cold weather conditions and optical inserts for soldiers with vision defects. The A1 had a mask to mask resuscitation feature that was found to expose personnel to chemical agents. This forced the services to withdraw it from issue and replace it with the A2 without the feature.

The mask offers protection from harmful agents, but does not function properly in places where oxygen content is low. The mask is not meant to be used for firefighting and does not provide protection from radiation. It is recommended that users continue wearing it until the biological or chemical agent is identified and cleared from the contaminated area.

The M-17 series protective masks were phased out in the 1990s, replaced by the M40 Field Protective Mask.