Shock Approach Boundary Calculator (NFPA 70E)
Look up limited, restricted, and prohibited approach boundaries for shock protection from NFPA 70E Tables 130.4(E)(a) and (b)
Free shock approach boundary calculator for electrical safety review conversations. Enter system voltage, AC/DC type, and fixed or movable conductor context to check the local limited and restricted boundary prompts already embedded in this app.
The output is not energized-work authorization, NFPA 70E compliance, OSHA compliance, PPE selection, LOTO verification, arc-flash boundary calculation, or a substitute for the employer electrical safety program and qualified-person review. Reconcile every local row against current licensed NFPA 70E text, equipment facts, site procedure, and qualified electrical/safety review before field use.
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Select AC or DC
Choose the voltage type for the local table prompt. Verify the voltage basis against equipment labels, drawings, and current source text before field use.
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Enter System Voltage
Enter the nominal voltage in volts. The app screens a local row only; it does not decide exposure, safe work, or compliance.
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Select Conductor Type
Choose fixed circuit part or movable conductor. Movable conductor context can involve overhead lines, sway, sag, tools, vehicles, and utility controls outside this app.
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Review Source Gaps
Use the warnings, source pointers, and residual gaps to route the output through NFPA 70E, OSHA, LOTO, arc-flash, PPE, employer-program, and qualified review.