Electric Shock Approach Boundaries Limited & Restricted Approach — AC and DC Systems
NFPA 70E 2027 Edition
How to read this chart: the limited approach boundary is the distance from an exposed energized conductor or circuit part that an unqualified person must not cross without proper supervision; the restricted approach boundary may be crossed only by qualified persons using the required shock protection. These shock boundaries are voltage-based. The arc flash boundary is separate — it is the distance at which incident energy falls to 1.2 cal/cm² (the onset of a curable second-degree burn) and is determined by the arc flash risk assessment, not by this chart. (For the arc flash boundary, see 130.5(E).)
AC Systems — Table 130.4(E)(a) · phase-to-phase voltage · distances are exposed part → personnel
Nominal system voltage (phase-to-phase)
Limited approach — exposed movable conductorc
Limited approach — exposed fixed circuit part
Restricted approach (incl. inadvertent movement adder)d
Less than 50 V
Not specified
Not specified
Not specified
50 V – 150 Ve
3.1 m (10 ft 0 in.)
1.0 m (3 ft 6 in.)
Avoid contact
151 V – 750 V
3.1 m (10 ft 0 in.)
1.0 m (3 ft 6 in.)
0.31 m (1 ft 0 in.)
751 V – 5 kV
3.1 m (10 ft 0 in.)
1.0 m (3 ft 6 in.)
0.63 m (2 ft 1 in.)
5.1 kV – 15 kV
3.1 m (10 ft 0 in.)
1.5 m (5 ft 0 in.)
0.65 m (2 ft 2 in.)
15.1 kV – 36 kV
3.1 m (10 ft 0 in.)
1.8 m (6 ft 0 in.)
0.77 m (2 ft 7 in.)
36.1 kV – 46 kV
3.1 m (10 ft 0 in.)
2.5 m (8 ft 0 in.)
0.84 m (2 ft 10 in.)
46.1 kV – 72.5 kV
3.1 m (10 ft 0 in.)
2.5 m (8 ft 0 in.)
1.0 m (3 ft 4 in.)
72.6 kV – 121 kV
3.3 m (10 ft 8 in.)
2.5 m (8 ft 0 in.)
1.2 m (3 ft 9 in.)
121.1 kV – 145 kV
3.4 m (11 ft 0 in.)
3.1 m (10 ft 0 in.)
1.3 m (4 ft 4 in.)
145.1 kV – 169 kV
3.6 m (11 ft 8 in.)
3.6 m (11 ft 8 in.)
1.5 m (4 ft 10 in.)
169.1 kV – 242 kV
4.0 m (13 ft 0 in.)
4.0 m (13 ft 0 in.)
2.1 m (6 ft 8 in.)
242.1 kV – 362 kV
4.7 m (15 ft 4 in.)
4.7 m (15 ft 4 in.)
3.5 m (11 ft 2 in.)
362.1 kV – 420 kV
5.8 m (19 ft 0 in.)
5.8 m (19 ft 0 in.)
4.3 m (14 ft 0 in.)
420.1 kV – 550 kV
5.8 m (19 ft 0 in.)
5.8 m (19 ft 0 in.)
5.1 m (16 ft 8 in.)
550.1 kV – 800 kV
7.2 m (23 ft 9 in.)
7.2 m (23 ft 9 in.)
6.9 m (22 ft 7 in.)
DC Systems — Table 130.4(E)(b) · nominal potential difference · note the DC voltage bands differ from AC
Nominal potential difference
Limited approach — exposed movable conductorc
Limited approach — exposed fixed circuit part
Restricted approach (incl. inadvertent movement adder)d
Less than 50 V
Not specified
Not specified
Not specified
50 V – 300 V
3.1 m (10 ft 0 in.)
1.0 m (3 ft 6 in.)
Avoid contact
301 V – 1 kV
3.1 m (10 ft 0 in.)
1.0 m (3 ft 6 in.)
0.3 m (1 ft 0 in.)
1.1 kV – 5 kV
3.1 m (10 ft 0 in.)
1.5 m (5 ft 0 in.)
0.5 m (1 ft 5 in.)
5.1 kV – 15 kV
3.1 m (10 ft 0 in.)
1.5 m (5 ft 0 in.)
0.7 m (2 ft 2 in.)
15.1 kV – 45 kV
3.1 m (10 ft 0 in.)
2.5 m (8 ft 0 in.)
0.8 m (2 ft 9 in.)
45.1 kV – 75 kV
3.1 m (10 ft 0 in.)
2.5 m (8 ft 0 in.)
1.0 m (3 ft 6 in.)
75.1 kV – 150 kV
3.3 m (10 ft 8 in.)
3.1 m (10 ft 0 in.)
1.2 m (3 ft 10 in.)
150.1 kV – 250 kV
3.6 m (11 ft 8 in.)
3.6 m (11 ft 8 in.)
1.6 m (5 ft 3 in.)
250.1 kV – 500 kV
6.0 m (20 ft 0 in.)
6.0 m (20 ft 0 in.)
3.5 m (11 ft 6 in.)
500.1 kV – 800 kV
8.0 m (26 ft 0 in.)
8.0 m (26 ft 0 in.)
5.0 m (16 ft 5 in.)
c. Exposed movable conductors describes a condition in which the distance between the conductor and a person is not under the control of the person — normally applied to overhead line conductors supported by poles.
d. Restricted approach distances are based on elevations not exceeding 900 m (3,000 ft); at higher elevations, adjustment of the restricted approach boundary shall be considered (see 29 CFR 1910.269 Table R-5, ANSI/IEEE C2, IEEE 516).
e. The 50 V – 150 V range applies to line-to-ground voltages up to 240 V.
For single-phase systems above 250 V, select the range equal to the system's maximum phase-to-ground voltage multiplied by 1.732. Source: NFPA 70E, 2027 edition, Tables 130.4(E)(a) and 130.4(E)(b). This poster is a training reference, not a substitute for the standard or a site-specific risk assessment.