Electrical Safety Sign Requirements: High Voltage, Panels, Eye Wash

Who sets the rules

OSHA's electrical standards are federal rules for employers. The National Electrical Code (NEC), published by NFPA, binds you only where a state or city has adopted it. ANSI standards come from industry committees, and OSHA treats them as guidance unless it adopts them.

The NEC edition depends on where you are. NFPA's map, dated August 3, 2026, lists Texas on the 2023 edition, Florida and Pennsylvania on 2020, Tennessee on 2017 with its own changes, and Colorado on 2026. California uses 2023 with amendments. Section numbers below follow what NFPA describes for the 2023 NEC, so ask your electrical inspector which edition governs your building.

High voltage sign wording

For buildings, rooms or enclosures with exposed live parts over 600 volts, 29 CFR 1910.303(h)(5)(iii) says entrances must stay locked unless a qualified person watches them. It also calls for permanent and conspicuous warning signs reading substantially “DANGER - HIGH VOLTAGE - KEEP OUT.” Staying with those three phrases is the safe choice.

The NEC sets its line higher. Section 110.34(C) covers locked rooms and enclosures with exposed live parts over 1,000 volts, and NFPA's electrical specialist says the door must carry “DANGER - HIGH VOLTAGE - KEEP OUT,” on a sign that also meets 110.21(B) on durability. So a room with exposed parts between 600 and 1,000 volts needs the DANGER wording under OSHA but only a general warning sign under the NEC.

Rooms with exposed live parts under 600 volts

Below those levels the rule is general. OSHA 1910.303(g)(2)(iii) says entrances to rooms and other guarded locations containing exposed live parts must be marked with conspicuous warning signs forbidding unqualified persons to enter. NEC 110.27(C) asks for the same kind of sign, placed on the door. Neither sets exact words, so the sign must say plainly that unqualified people may not enter.

The rule is about exposed live parts. A closed panel in a hallway may not trigger it, while a room with open gear does. Your safety officer or inspector can say whether your room counts. Browse electrical room signs, high voltage authorized personnel signs and authorized personnel only signs.

OSHA 1910.145 names Danger signs for immediate danger and Caution signs for potential hazards or unsafe practices. In the ANSI Z535 system, Danger means a hazard that will cause death or serious injury if not avoided, Warning means it could, and Caution means minor or moderate injury. OSHA's high voltage wording starts with DANGER. The rules asking for “warning signs” do not name a header word.

Electrical panels: what is required

For panels the duty is about space, not a sign. OSHA 1910.303(g)(1) requires sufficient working space about electric equipment, and (g)(1)(ii) says it may not be used for storage. At 600 volts or less the space must be as wide as the equipment or 30 inches, whichever is greater, with 6.5 feet of headroom on installations built since August 13, 2007. Doors must open at least 90 degrees.

Depth comes from Table S-1: 3 feet up to 150 volts to ground, and 3, 3.5 or 4 feet from 151 to 600 volts, depending on what sits across from the panel. NFPA describes the NEC's 110.26 with a width of at least 30 inches and table depths from 3 to 5 feet. So 30 by 36 inches is a floor, and some panels need more.

Is a keep clear sign required? Not in the OSHA text or the NFPA articles we read. The rule is to keep the space clear, and it names no sign or floor marking. A sign or floor tape is good practice, and your inspector or employer may ask for one. What is required is a legible label at each breaker or disconnect saying what it controls (1910.303(f)(2)). See electrical panel keep clear signs.

Arc flash labels are a different product

NEC 110.16 asks that equipment such as switchboards, panelboards, industrial control panels and motor control centers, outside dwelling units and likely to be serviced while energized, be marked to warn qualified persons of arc flash hazards. Service and feeder equipment rated 1,000 amperes or more also gets a dated label. NFPA's committee draft for the 2026 edition proposed widening this, so check your edition.

These labels carry facts about your own equipment. NFPA points to NFPA 70E for labels showing system voltage, incident energy, arc flash boundaries and protective equipment levels, which come from an assessment, so a general printed sign cannot stand in. A 2006 OSHA letter says OSHA has no specific arc flash marking rule, though 1910.335(b)(1) requires signs where needed to warn of electrical hazards.

Eye wash station signs

OSHA 1910.151(c) says that where the eyes or body of any person may be exposed to injurious corrosive materials, suitable facilities for quick drenching or flushing must be provided within the work area for immediate emergency use. It mentions no sign and does not define “suitable,” which is why the ANSI standard matters.

ANSI/ISEA Z358.1 is a consensus standard for eyewash and shower equipment. OSHA's rule does not name it, and a 2002 OSHA letter says ANSI standards become mandatory only if OSHA adopts them. The same letter says OSHA may look at the latest edition when judging whether a station is suitable. ISEA, which develops the standard, says many states and the model plumbing codes refer to it, so check yours.

ISEA says the standard calls for equipment to be identified with appropriate signage and reached within 10 seconds. Its checklist asks whether a highly visible sign shows the location and whether the area is well lit. ANSI Z535.2 has a sign type for locating safety equipment such as eyewash stations and safety showers. See eye wash station signs.

Choosing signs and checking your rules

For exposed parts over 600 volts, use the OSHA wording on high voltage signs. Mark equipment with electrical hazard signs, and use Spanish high voltage signs where crews read Spanish. See all safety signs. Our designs use the ANSI Z535 header style, and every sign can carry your own line of text.

Before you order, ask your safety officer or electrical inspector about the voltage and whether live parts are exposed, which NEC edition applies, what wording they want on the door, and whether each eyewash station needs a sign. This guide explains the rules in plain words and is not legal advice.

Common questions

Sources

• OSHA, 29 CFR 1910.303, General (eCFR): paragraphs (f)(2), (g)(1), (g)(2)(iii), (h)(5)(iii) and Table S-1
• OSHA, 29 CFR 1910.145, Specifications for accident prevention signs and tags (eCFR)
• OSHA, 29 CFR 1910.151, Medical services and first aid (eCFR), paragraph (c)
• OSHA letter of interpretation, November 14, 2006: arc flash marking, NFPA 70E, and 1910.335(b)
• OSHA letter of interpretation, November 1, 2002: ANSI Z358.1 and 1910.151(c)
• NFPA, Electrical Rooms Part 2 by Dean Austin, December 21, 2022 (NEC 110.26, 110.27(C), 110.34, 110.21(B))
• NFPA, NEC Code-Making Panel 1 working draft for the 2026 edition, which prints the current text of 110.16 and 110.34(C)
• NFPA, Learn where the NEC is enforced (state-by-state edition table, as of August 3, 2026)
• ANSI Blog, ANSI Z535.2-2023: Facility/Environment Safety Signs (hazard classes and sign types)
• International Safety Equipment Association, Emergency Eyewash & Shower Equipment Selection, Installation & Use Guide, 2024 (ANSI/ISEA Z358.1)

This guide explains the rules in plain words; it is not legal advice. We read the sources above on October 24, 2026. Rules change and many are set by your state or city: check the current text, or ask your local code official, before you rely on it.