Valve Tag Standards: ASME A13.1, Content & Materials

If you've gone looking for "the valve tag standard," you've discovered there isn't a dedicated one. Valve identification is governed by the pipe-marking standard it belongs to, plus OSHA's expectation that hazards are identified. Here's how the pieces fit, what goes on a compliant tag, and how to choose a material that survives.

The governing standard is ASME A13.1

Valve tagging is tied to ANSI/ASME A13.1, the Scheme for Identification of Piping Systems (current edition A13.1-2020). OSHA doesn't publish its own pipe-labeling standard, but it incorporates A13.1 by reference and can cite inadequate identification under the General Duty Clause, so following A13.1 is the accepted way to demonstrate compliance. In process facilities, valves also intersect ASME B31.3 (process piping) and ISA-5.1 (instrumentation), both of which expect valves to be identifiable and traceable.

The color code

A13.1 ties tag and marker colors to pipe contents: red/white for fire-quenching fluids, orange/black for toxic and corrosive, yellow/black for flammable and oxidizing, brown/white for combustible, green/white for water, and blue/white for compressed air. The standard reserves additional colors for facility-defined uses, so confirm whether your site follows the standard scheme or a facility-specific one.

What belongs on the tag

A compliant tag carries a unique valve number or ID matching the facility P&ID, a plain-language service description (e.g. "Chilled Water Supply"), and the normal operating position — NO for normally open, NC for normally closed. Some facilities add the P&ID reference or an inspection date. One rule that trips people up: the tag attaches to the valve body, never the handle.

Choosing the material

Match the tag to the environment. Brass and stainless handle high-temperature, chemical, and outdoor exposure; aluminum suits moderate conditions; plastic is fine only for low-hazard indoor use. Across all of them, engraved tags outlast printed ones — engraved traffolyte and engraved metal legends won't fade, peel, or smear the way surface printing does. For a documented valve schedule that must pass an audit years from now, that permanence is the point.

Custom Phenolic Labels engraves valve tags and matching legends in laminate, brass, stainless, and aluminum — sequentially numbered to your valve schedule and ready to match your P&ID.

Frequently asked questions

Is there one dedicated valve tag standard?

Valve identification generally follows the piping identification system, facility standards, and applicable safety requirements.

What belongs on a valve tag?

A unique ID tied to the P&ID, a service description, and the normal operating position are common requirements.

Plan the complete identification package

Use these connected guides and services to confirm the material, code reference, mounting method, and order details: Engraved Nameplates, Tags & Lamacoid Labels, Arc Flash Labels vs. Permanent Equipment, and Mount Engraved Labels So They Last.