scope:

PREFACE

This publication represents a basic standard for safe operation, substantial and durable construction, and acceptable performance of automatic valves for gas appliances. It is the result of years of experience in the utilization of gas, supplemented by extensive research.

Nothing in this standard is to be considered in any way as indicating a measure of quality beyond compliance with the provisions it contains. It is designed to allow compliance of automatic valves for gas appliances, the construction and performance of which may exceed the various provisions specified herein. In its preparation, full recognition has been given to possibilities of improvement through ingenuity of design. As progress takes place, revisions may become necessary. When they are believed desirable, recommendations should be forwarded to the Chairman of Accredited Standards Committee Z21, 8501 East Pleasant Valley Road, Cleveland, Ohio 44131.

Safe and satisfactory operation of an automatic valve for gas appliances depends to a great extent upon its proper installation, and it should be installed in accordance with the National Fuel Gas Code, ANSI Z223.1; manufacturers' installation instructions and local municipal codes.

Users of this American National Standard are advised that the Devices/products/activities within its scope may be subject to regulation at the Federal, state or local level. Users are strongly urged to investigate this possibility through appropriate channels. In the event of a conflict with this standard, the Federal, state or local regulation should be followed.