C4

An older, rarer, black version C4

Preceded by	Succeeded by
C3	C5

Made in

Canada

Period

1980s-Current

Issued to

Canadian Forces

Fire and Rescue Department of Malaysia

Angkatan Pertahanan Awam Malaysia

Malaysian army

Ejército Nacional (National Army of Uruguay)

Manufacturer

- DREO (Defense Research Establishment of Ottawa)

- Airboss

The Canadian C4 is the current issue respirator of the Canadian armed forces, but is being slowly replaced by the C5. The Defense Research Establishment of Ottawa (DREO), production started in the 1980s and the mask serves as an excellent example of the "Fourth Generation Respirator".

The mask[]

Early C4's were produced by DREO in both black and green. C4's produced by DREO had quality issues and were known to break easily. Production switched to Airboss in 1992.

The Canadian C4 has convex dual polycarbonate eyepieces that provide a reasonable field of vision, in contrast to masks with circular flat lenses.

AAAGAS-41-3 — The profile of a more common green C4 gas mask. Note the drinking tube and the head strap.

The mask itself is made of bromo-butyl rubber. A voice diaphragm is located beneath the eyepieces, and more modern versions include drinking straws. The filter canisters can be attached on the right or left side, allowing both left and right handed users to sight weapons. Astride of the voice diaphragm is either an exhale valve or an inlet valve, depending on the model. The mask has a six-point fabric head harness, with only two adjustable straps, the adjustable being the bottom ones below the user's ears.

The C4 surpasses NATO and related Triptych requirements for face, eyes and respiratory tract protection against chemical and biological warfare agents when used with an approved filter/canister.

It should be noted that C4 masks that are no longer used for military service are often “demilitarized,” a process in which the facepiece is cut so that they cannot be used anymore. Demilitarized masks are commonly “repaired” by securing the strap to the mask through use of pins, staples, or similar means.

Gallery[]

Aircrew variant[]

The AC4 was made for use by aircrew. The facepiece differs from the regular type by having a microphone port on the left, the drinking tube on the right side instead of the left and a plug on the voice diaphragm. The mask comes with a hose connecting to a PAPR with a double filter inlet. The AC4 is based off of the early C4 and was replaced by the AR-5.