Shock Approach Boundaries (NFPA 70E Table 130.4)

Looks up the NFPA 70E Table 130.4 AC shock approach boundaries by nominal voltage.

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Example

You enter

Nominal voltage (phase-to-phase, AC) 151-750 V

You get

Limited approach - fixed circuit part 3 ft 6 in
Restricted approach 1 ft 0 in
No boundary No

Details, formula, and sources

The limited approach (separate distances for an exposed movable conductor vs a fixed circuit part) and the restricted approach. Below 50 V no boundary is specified. Shock boundaries only (the arc-flash boundary is separate); the employer's safety program and 70E govern.

lookup by nominal phase-to-phase AC voltage band: limited approach (exposed movable conductor vs exposed fixed circuit part) and restricted approach; below 50 V no boundary is specified.

AC shock approach boundaries, NFPA 70E-2024 Table 130.4, by name.

NFPA 70E is free to read at nfpa.org/freeaccess. These are shock boundaries only; the arc-flash boundary is a separate determination. Crossing the restricted approach requires a qualified person, an energized-work permit, and shock PPE.

Estimate. AHJ and licensed electrician govern. Verify against the NEC edition adopted in your jurisdiction.

Field names used by the API: nominal_v_ac, limited_fixed, restricted, no_boundary

Limited approach the boundary an unqualified person must not cross; the larger distance applies to an exposed movable conductor, the smaller to an exposed fixed circuit partNFPA 70E Table 130.4
Restricted approach the boundary requiring a qualified person, an energized-work permit, and shock PPE to crossNFPA 70E Table 130.4