Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
ANSI Z21.92b-2010 / CSA 6.29b-2010: Manually Operated Gas Valves for Appliances, Appliance Connector Valves, and Hose End Valves
Key Technical Requirements, Testing Protocols, and Compliance Insights for Gas Valve Manufacturers and Safety Inspectors
The American National Standard ANSI Z21.92b-2010 / CSA 6.29b-2010 establishes uniform requirements for manually operated gas valves used in residential and commercial gas appliances, appliance connectors, and hose-end applications. This dual standard, developed jointly by the American National Standards Institute (ANSI) and the Canadian Standards Association (CSA), serves as the primary benchmark for safety, performance, and interchangeability of gas shut-off valves in North America. Manufacturers, testing laboratories, and installers rely on this standard to ensure valves operate reliably under normal and abnormal conditions, reduce leakage risks, and provide consistent user experience across a wide range of gas types and pressures.
Scope and Application
The standard covers three main categories of manually operated valves:
- Appliance valves — valves intended for direct mounting on gas appliances (e.g., ranges, ovens, water heaters) that control gas flow to burners.
- Appliance connector valves — valves installed in the gas supply line between a shut-off point and an appliance, typically used with flexible connectors.
- Hose end valves — hand-operated valves attached to the free end of a gas hose (e.g., for outdoor grills, portable heaters, or laboratory equipment).
Valves may be designed for use with natural gas, liquefied petroleum (LP) gas, manufactured gas, or mixed gases. The standard applies to valves of any size, provided they are intended for manual operation (hand-wheel, lever, or push-turn mechanism) and are not automatically actuated. It does not cover gas valves that are electrically operated, thermostatically controlled, or otherwise automated—those fall under separate standards such as ANSI Z21.78 or ANSI Z21.21.
The 2010b edition includes supplemental requirements for valve stem sealing, enhanced flow testing, and updated marking provisions that reflect industry feedback and field failure analysis. All valves manufactured after the effective date must comply with the latest supplement or the base standard unless otherwise accepted by the certifying body.
Important: The standard distinguishes between valves intended for indoor use (e.g., on a gas range) and those for outdoor or semi-exposed installations (e.g., grill valves). The latter must meet additional corrosion resistance and weatherproofing requirements not explicitly covered in the base Z21.92 edition.
Technical Requirements
Construction and Materials
All valves must be constructed from materials compatible with the intended gas and capable of withstanding a proof pressure of 50 psi (345 kPa) without leakage or permanent deformation. The standard specifies:
| Component | Material Requirement | Remarks |
|---|---|---|
| Valve body | Brass, bronze, stainless steel, or corrosion-resistant zinc-aluminum alloy | Cast or forged, no porosity leaks allowed |
| Valve stem | Corrosion-resistant metal or high-strength polymer | Must resist wear after 10,000 cycles |
| Seats and seals | Elastomeric or polymeric compounds | Grade hardened to resist gas permeation |
| Handle/knob | Metal or thermoplastic | Indelible marking of knob position |
Performance Criteria
Every valve must pass a battery of tests, the most critical of which are leakage tests performed at both low (6–8 inches w.c.) and high (25 psi) pressures. The allowable leakage rates are strictly limited:
- Low-pressure leakage (gas volume): ≤ 0.060 cubic feet per hour (ft³/h) of air at 6–8 inches w.c.
- High-pressure leakage (gas volume): ≤ 0.120 ft³/h at 25 psi, or ≤ 0.066 ft³/h for valves rated below 1/2″ NPT.
In addition, valves must exhibit no structural failure when subjected to a proof pressure test of 50 psi for 1 minute, and no external leakage when held at 30 psi (valve closed) for 1 minute.
Testing and Validation
The standard prescribes detailed test methods, including torque resistance for valve handles, cycle endurance (6,000 full-open-to-full-close cycles for nominal sizes up to 1 inch; 1,500 cycles for larger sizes), and a hydrostatic strength test for valves intended for remote or outdoor use. The valve handle must be designed to withstand a torque of 5 ft-lbf (6.8 N·m) without permanent deformation.
Tip for manufacturers: When selecting seal materials, pay attention to the low temperature requirement (-20°C / -4°F) for valves that will be shipped to cold climate regions. Standard elastomers may become brittle and fail the cycling test. Silicone or fluorocarbon compounds are recommended.
Compliance and Certification
Certification to ANSI Z21.92b-2010 / CSA 6.29b-2010 can only be performed by an accredited third-party laboratory (e.g., CSA, UL, Intertek). The certification process includes:
- Initial type testing of samples from a production batch
- Factory inspection and quality assurance review
- Periodic follow-up testing (typically once per year) of production samples
- Required modification of the valve when any design change could affect safety or performance
Once certified, the valve must bear a permanent marking indicating:
- Manufacturer’s name or trademark
- Valve model number or part number
- Gas type designation (NG or LP or both)
- Maximum working pressure (in psi or kPa)
- Closing direction (OFF or SHUT indicator, plus rotation arrow)
- Standard reference: “ANSI Z21.92 / CSA 6.29”
Compliance advantage: A valve that carries the certification mark of a recognized testing laboratory (e.g., CSA Blue Star) automatically satisfies the requirements of most local gas codes (including NFPA 54/ANSI Z223.1 and CSA B149.1), streamlining approval for installation in both the United States and Canada.
Implementation Best Practices
For manufacturers designing new valves or modifying existing products to comply with the 2010b supplement, the following points deserve attention:
- Handle orientation: The valve must be designed so that the handle’s “OFF” position is clearly indicated, and there is no ambiguity when the valve is in the closed position. A positive stop mechanism is required.
- Flow coefficient (Cv) documentation: The standard does not mandate a minimum Cv, but many appliance OEMs require it. It is good practice to publish Cv values (or equivalent flow curves) in the product specification sheet.
- Sealant and thread compound: Tapered pipe threads must be coated with an appropriate sealant that does not dissolve in the gas. The standard prohibits the use of thread tape on internal valve threads unless it is factory-applied and approved.
- Spring-loaded handles (if used): For hose end valves that incorporate a spring-return to the closed position (e.g., self-closing type), additional cycle testing is required—the standard requires 25,000 cycles for such mechanisms.
Non-compliance risk: A valve that does not meet the leakage limits listed above poses a serious fire or explosion hazard. Field failures due to improperly seated seals or inadequate stem retention have been linked to several gas appliance incidents. Always verify that your valve design has passed the hydrostatic and thermal cycling tests at an accredited laboratory.
Transition from Earlier Editions
The 2010b supplement introduced modifications to table values for leakage rates and increased the handle torque requirement from 4.5 to 5 ft-lbf. If your company previously certified valves under ANSI Z21.92-2009 / CSA 6.29-2009 (base edition), it is essential to review the updated test tables and marking specifications. Valves certified under the earlier edition may need to be retested and re-marked before they can be sold as compliant with the 2010b supplement.
Frequently Asked Questions
Q: Does ANSI Z21.92b-2010 / CSA 6.29b-2010 cover all types of manual gas valves?
A: No. The standard specifically covers appliance valves, appliance connector valves, and hose end valves. It does not apply to valves that are automatic, thermostatically controlled, or intended for gas shut-off at the meter (which fall under ANSI Z21.15). Additionally, valves rated above 5 psi working pressure are not covered and must comply with ASME B16.33 or similar standards.
A: No. The standard specifically covers appliance valves, appliance connector valves, and hose end valves. It does not apply to valves that are automatic, thermostatically controlled, or intended for gas shut-off at the meter (which fall under ANSI Z21.15). Additionally, valves rated above 5 psi working pressure are not covered and must comply with ASME B16.33 or similar standards.
Q: Can a valve certified to an older edition (e.g., 2003) still be used in new installations?
A: In most jurisdictions, building and gas codes require compliance with the latest edition of referenced standards. Unless a local amendment specifically permits the older edition, valves must meet the current edition (including supplements) to be legally installed. Some regulatory authorities allow a grace period of 6–12 months after publication of a supplement.
A: In most jurisdictions, building and gas codes require compliance with the latest edition of referenced standards. Unless a local amendment specifically permits the older edition, valves must meet the current edition (including supplements) to be legally installed. Some regulatory authorities allow a grace period of 6–12 months after publication of a supplement.
Q: What is the difference between the “b” supplement and the base standard?
A: The “b” supplement is an amendment to the base edition (Z21.92-2009). It contains revised test pressures, updated leakage tables, and additional marking requirements that address concerns raised by the gas industry. The supplement is integrated into the standard when the title includes the “b” suffix. After the supplement becomes effective, compliance must be demonstrated to the combined standard edition.
A: The “b” supplement is an amendment to the base edition (Z21.92-2009). It contains revised test pressures, updated leakage tables, and additional marking requirements that address concerns raised by the gas industry. The supplement is integrated into the standard when the title includes the “b” suffix. After the supplement becomes effective, compliance must be demonstrated to the combined standard edition.
Q: Are plastic or polymer-bodied valves allowed under this standard?
A: Yes, but only for low-pressure applications (≤ 0.5 psi) and after passing additional temperature cycling and ultraviolet exposure tests if the valve is intended for outdoor use. The standard does not preclude the use of engineering plastics, but the certification body will require evidence of long-term resistance to gas permeation and environmental stress cracking.
A: Yes, but only for low-pressure applications (≤ 0.5 psi) and after passing additional temperature cycling and ultraviolet exposure tests if the valve is intended for outdoor use. The standard does not preclude the use of engineering plastics, but the certification body will require evidence of long-term resistance to gas permeation and environmental stress cracking.
Published: 2026 — This article is intended for educational and informational purposes. Always refer to the full text of ANSI Z21.92b-2010 / CSA 6.29b-2010 (available from ANSI or CSA Group) for exact language and legal requirements.