1.1''This specification2 covers the application, design, and materials for valve locking devices.

1.2''Locking devices Types I and II described in this specification are designed to secure the valve in a fully opened or completely closed position.

1.3''This specification does not apply to valves equipped with locking devices from the valve manufacturer, unless this standard is invoked in the procurement ordering data for the valve or its locking device, or both.

1.4''The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.

1.5''This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.