---
title: "What equipment selection, installation, and grounding requirements does 29 CFR 1910.254 impose on arc welding and cutting equipment? Answer in under 100 words. Cite only eCFR (www.ecfr.gov) sources."
canonical: https://www.m-i-n-d.ai/minds/welding/equipment-selection-installation-grounding-requirements-29-cfr-1910-254-impose
jurisdiction: "US Federal · OSHA General Industry"
last_verified: 2026-08-26
license: CC BY 4.0 — https://creativecommons.org/licenses/by/4.0/
attribution: "Source: MIND (m-i-n-d.ai)"
---

# What equipment selection, installation, and grounding requirements does 29 CFR 1910.254 impose on arc welding and cutting equipment? Answer in under 100 words. Cite only eCFR (www.ecfr.gov) sources.

Under 29 CFR 1910.254, welding equipment must be chosen for safe application to the specific task, with design assurance met by apparatus complying with NEMA EW-1-1962 or ANSI C33.2-1956. Voltage limits are 80 volts for manual AC welding and 100 volts for automatic AC and all DC machines. Installation, including power supply, must follow Subpart S electrical standards of 29 CFR Part 1910, and the machine frame or case must be grounded accordingly. Conduits containing electrical conductors may not complete a work-lead circuit, pipelines cannot be permanent work-lead parts, and chains, wire ropes, cranes, hoists, and elevators must never carry welding current.

## Equipment selection

Employers must choose welding equipment for safe application to the specific welding or cutting task to be performed [ref_id 1]. Assurance of safety in design is obtained by selecting apparatus complying with **NEMA EW-1-1962** (*Requirements for Electric Arc-Welding Apparatus*) or **ANSI C33.2-1956** (*Safety Standard for Transformer-Type Arc-Welding Machines*), both incorporated by reference [ref_id 1].

## Voltage limits

| Machine type | Maximum open-circuit voltage |
|---|---|
| Manual AC | 80 volts |
| Automatic (machine/mechanized) AC | 100 volts |
| Manual DC | 100 volts |
| Automatic (machine/mechanized) DC | 100 volts |

Higher-voltage special processes require adequate insulation or other means preventing operator contact, and reliable automatic no-load voltage reduction controls are recommended for AC welding in wet conditions or where perspiration is a factor [ref_id 1].

## Installation & grounding requirements

- Installation, including power supply, must comply with **Subpart S of 29 CFR Part 1910** (Electrical standards) [ref_id 1].
- The **frame or case** of each welding machine (except engine-driven machines) must be grounded under the conditions and methods prescribed in Subpart S [ref_id 1].
- All ground connections must be checked to confirm they are mechanically strong and electrically adequate for the required current [ref_id 1].
- Conduits containing electrical conductors must **not** be used to complete a work-lead circuit; pipelines may be used only temporarily during construction, extension, or repair, provided current does not pass through threaded, flanged bolted, or caulked joints [ref_id 1].
- Chains, wire ropes, cranes, hoists, and elevators must never be used to carry welding current [ref_id 1].
- A disconnecting switch or controller must be provided at or near each machine lacking an integral switch, with overcurrent protection per Subpart S [ref_id 1].

## Exceptions & edge cases

- Engine-driven welding machines that are not connected to a supply circuit are exempt from the frame-grounding requirement [ref_id 1].
- Pipelines may serve a work-lead circuit on a temporary basis during construction, extension, or repair if special precautions avoid sparking at the work-lead cable connection [ref_id 1].
- Structures, conveyors, or fixtures regularly used as a welding return circuit must have joints bonded or fitted with adequate current-collecting devices [ref_id 1].
- For multiple welders on one structure, all DC machines must share the same polarity, and all AC machines must connect to the same supply phase with identical instantaneous polarity [ref_id 1].

## Sources

- [1] U.S. National Archives, Electronic Code of Federal Regulations — 29 CFR 1910.254 — Arc welding and cutting · https://www.ecfr.gov/current/title-29/section-1910.254 · as of 2026-08-26