A synthetic rubber with excellent ozone, weathering, and acid resistance. Widely used in fire hose to retard abrasion.

Indentation on the inside of a hose coupling in which a rubber gasket is installed to provide the seal between the hose jacket, coupling, and expansion ring.

Engine work capacity. One horsepower (hp) equals 33,000-ft/lb work per minute. (Gross hp is directly off the engine drive shaft; net hp includes power remaining after power to accessories is subtracted.)

Removal of the first (i.e., outside) thread of a female or male coupling to prevent crossing or mutilation of threads. Dimpled rocker lug on female coupling indicates beginning of Higbee Cut.

Pressure due to elevation of water. Equals 0.433 psi per foot of elevation. Back pressure.

A code that indicates the fitness level of a human resource.

The ratio of the input driving element (shaft) to the output element (shaft).

The process by which the tube is bonded 360 degrees around within the jacket.

The result of turbulence within the water (fluids) and the resistance along the inside wall of fire hose or pipe.

Spring action check valve usually used at the lower end of suction hose often incorporating a strainer.