Reference / Working Space
Quick reference · Grade G
Working Space (OSHA)
The clear depth required in front of electrical equipment that may be examined, adjusted or serviced while energized.
Minimum depth of clear working space metres / feet
| Nominal voltage to ground | Condition A | Condition B | Condition C |
|---|---|---|---|
| 0–150 V | 0.9 m · 3 ft | 0.9 m · 3 ft | 0.9 m · 3 ft |
| 151–600 V | 0.9 m · 3 ft | 1 m · 3.5 ft | 1.2 m · 4 ft |
| 601–2,500 V | 0.9 m · 3 ft | 1.2 m · 4 ft | 1.5 m · 5 ft |
| 2,501–9,000 V | 1.2 m · 4 ft | 1.5 m · 5 ft | 1.8 m · 6 ft |
| 9,001 V–25 kV | 1.5 m · 5 ft | 1.8 m · 6 ft | 2.8 m · 9 ft |
| Over 25–75 kV | 1.8 m · 6 ft | 2.5 m · 8 ft | 3 m · 10 ft |
| Above 75 kV | 2.5 m · 8 ft | 3 m · 10 ft | 3.7 m · 12 ft |
- Voltages are nominal voltage to ground.
- For 600 V or less, the working space must be at least as wide as the equipment or 762 mm (30 in), whichever is greater, and headroom at least 1.98 m (6.5 ft) for installations made on or after August 13, 2007.
- The NEC (Article 110.26 and 110.34) carries its own, similar clearance rules; the stricter of the adopted code and OSHA applies.
Source: 29 CFR 1910.303(g)(1), Table S-1, and 1910.303(h)(3), Table S-2. © RokBench.