Canadian Armed Forces Nerve Agent Vapor Detector (NAVD)

The Canadian Armed Forces has developed and taken into service a simple, inexpensive, expendable device for the detection of dangerous concentrations of nerve gas vapours, which requires a minimum of training to use. Because this item is on issue to the individual soldier, it is designed to be simple, low cost and small in size.

Its use is two-fold: a) To quickly determine if a chemical attack detected by a "gas alarm" system is dangerous in the immediate vicinity of the individual; b) To quickly determine when it is safe for an individual to unmask. The chemical reaction is of the fail-safe type. The detector consists of two main parts — a plastic body containing an enzyme impregnated test paper; and a plastic holder containing a chemically impregnated test paper. When the test paper in the body is moistened, exposed to the atmosphere and then pressed in contact with the test paper in the holder, the test paper in the body will change colour to blue or green in the absence of nerve agent vapour. If nerve agent vapour is present the colour of the test papers will remain unchanged after contact with each other. The detector, which is 8.9 x 2.9 x 0.65 cm, is packaged in an airtight, moisture-proof foil wrap for protection against environmental conditions t -di' required for use.