CSA/AM ANSI/IAS NGV 4.4-1999/CSA 12.54-M99

Abstract

This standard applies to newly produced compressed Natural Gas Vehicle (NGV) dispenser shear valves and fueling hose emergency breakaway shutoff devices, hereinafter referred to as devices. <br>[It is not applicable to "Vehicle Refueling Appliances".] <br>Devices covered by this standard are intended to: <br>1. a. Minimize the escape of natural gas by automatically shutting off the flow of gas from the dispenser and control the depressurization of the hose, and; <br>b. Minimize damage to the vehicle and dispenser when a vehicle is driven off with the nozzle attached to the vehicle's fueling receptacle. <br>2. Automatically shut off the flow of gas in the event of a vehicular collision with a fuel dispenser that results in the displacement of the dispenser from its gas supply connection. <br>All dimensions used in this standard are in metric units [International System of Units (SI)], unless otherwise specified. If a value for a measurement, as given in this standard, is followed by an equivalent value in other units, the first stated is to be regarded as the specification. <br>All references to pressure throughout this document are to be considered gauge pressures unless otherwise specified.