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CSA ANSI LC 6-08 (2018) – Regulator and Port Adaptors for LP‑Gas Cylinders with Integral Valves
Technical Requirements, Scope, and Compliance Guidance for Fuel System Safety
Scope and Application
CSA ANSI LC 6-08 (2018) establishes the minimum requirements for regulator and port adaptors used in conjunction with LP‑gas cylinders that are equipped with integral valves. Integral valves are defined as service valves that incorporate a pressure relief device and are attached directly to the cylinder collar. These adaptors facilitate the connection between the cylinder valve outlet and the first‑stage regulator or service appliance. The standard applies to both Type A (regulator adaptors) and Type B (port adaptors) components, covering dimensions, thread forms, materials, torque limits, and performance criteria.
The standard was developed jointly by CSA Group and ANSI and is recognized by regulatory authorities in Canada and the United States. It is intended to ensure interchangeability and safe operation across different equipment manufacturer platforms. The 2008 edition reaffirmed in 2018 includes clarifications on thread verification and updated references to material specifications.
Technical Requirements
Design and Construction
All adaptors covered by this standard must be fabricated from corrosion‑resistant materials, typically brass or stainless steel, that are compatible with LP‑gas service. The connections shall conform to SAE J512 taper threads for flare connections or NPT taper pipe threads as specified for internal/external ports. Dimensional specifications for the adaptor body, including length, hex size, and shoulder dimensions are prescribed to ensure compatibility with standard cylinder valves and regulator inlets.
Table 1 summarizes principal dimensional requirements for the most common adaptor types:
| Adaptor Type | Thread Size (Inch) | Hex Size (in.) | Min. Flow Area (in²) | Max. Torque (lbf·ft) |
|---|---|---|---|---|
| Type A – Regulator Adaptor (CGA 500) | 1/4-18 NPTM × 1/4-28 SAE | 0.75 | 0.031 | 15 |
| Type B – Port Adaptor (CGA 502) | 5/16-24 SAE × 1/4-28 SAE | 0.88 | 0.045 | 12 |
| Type C – Extended Adaptor (CGA 510) | 5/8-18 UNF × 7/16-20 SAE | 1.00 | 0.062 | 18 |
| Type D – Swivel Adaptor | 3/8-24 SAE × 1/4-28 SAE | 0.94 | 0.040 | 15 |
Table 1: Dimensional and torque criteria for selected adaptors per CSA ANSI LC 6-08 (2018).
Performance Testing
Each adaptor design must undergo a series of qualification tests including a hydrostatic pressure test at 1.5 times the maximum allowable working pressure, thermal cycling between −40°F and +140°F (−40°C to +60°C), and a gas leak test using sensitive tracer gas or bubble emission methods. Additionally, a torque retention test verifies that the adaptor remains leak‑tight after repeated connection cycles.
Design Tip: For reliable sealing during thermal extremes, select O‑ring materials rated for continuous service at temperatures exceeding 140°F (60°C). Viton® or FKM compounds are recommended for low‑temperature conditions below −40°C.
Marking and Identification
Every adaptor must be permanently marked with the manufacturer’s name or trademark, the designation “LC 6” or “CSA ANSI LC 6-08”, and the maximum allowable operating pressure in psig. Markings must remain legible after exposure to the abrasion and solvent resistance tests specified in the standard.
Compliance and Certification
Manufacturers seeking to certify products to CSA ANSI LC 6-08 (2018) must submit representative samples to an accredited third‑party laboratory (e.g., CSA Group, UL) recognized by the Standards Council of Canada or the American National Standards Institute. Successful completion of all design, performance, and marking requirements—together with an initial factory inspection—authorizes the manufacturer to apply a certification mark (e.g., CSA monogram or UL listing).
Important: Although the standard was reaffirmed in 2018, manufacturers should verify that elastomeric components comply with the latest revisions of referenced ASTM D2000 calls, as some material grades may have been upgraded. Certifiers must be notified of any material or process changes that could affect conformance.
Periodic unannounced follow‑up inspections by the certifying body are required to maintain the listing. Records of production tests, including batch leak checks and material certifications, must be retained for at least five years and made available upon request.
Compliance Benefit: Products bearing a recognized mark for CSA ANSI LC 6-08 (2018) are automatically accepted under Canadian TP‑180 regulations and in most U.S. states that adopt NFPA 58, minimising the need for redundant certifications.
Non-Compliance Risk: Use of adaptors without a valid certification mark can lead to code violations, insurance denial, and gas leaks resulting in fire or explosion. Authorities in both Canada and the United States may impose fines and removal orders for unlisted components.
Frequently Asked Questions
Q: What does “integral valve” mean in the context of CSA ANSI LC 6-08 (2018)?
A: An integral valve is a cylinder service valve that includes a built‑in pressure relief device and is permanently attached to the cylinder. These valves are common on forklift and industrial LP‑gas cylinders. The standard covers adaptors that connect directly to such valves.
A: An integral valve is a cylinder service valve that includes a built‑in pressure relief device and is permanently attached to the cylinder. These valves are common on forklift and industrial LP‑gas cylinders. The standard covers adaptors that connect directly to such valves.
Q: Is CSA ANSI LC 6-08 (2018) aligned with any CGA standards?
A: Yes. The standard references CGA V‑1 (Standard for Compressed Gas Cylinder Valve Outlet and Inlet Connections) for thread and connection dimensions. The adaptor types listed in Table 1 correspond to CGA connection numbers such as CGA 500, CGA 502, and CGA 510.
A: Yes. The standard references CGA V‑1 (Standard for Compressed Gas Cylinder Valve Outlet and Inlet Connections) for thread and connection dimensions. The adaptor types listed in Table 1 correspond to CGA connection numbers such as CGA 500, CGA 502, and CGA 510.
Q: How frequently must a certified adaptor be re‑tested?
A: The initial type test is performed on a representative sample. Subsequent production lots must undergo batch leak tests as defined in the manufacturer’s quality plan. A full type test is only required after a design or material change. Certification bodies conduct annual factory audits to confirm ongoing compliance.
A: The initial type test is performed on a representative sample. Subsequent production lots must undergo batch leak tests as defined in the manufacturer’s quality plan. A full type test is only required after a design or material change. Certification bodies conduct annual factory audits to confirm ongoing compliance.
For complete details, consult the full normative text of CSA ANSI LC 6-08 (2018), available from CSA Group or ANSI. © 2026 – All rights reserved. This article provides an informative summary and does not substitute the official standard.