Warning sign - yellow triangle
High voltage signs
A high voltage sign warns that a supply can seriously harm or kill, and it often states how much. These printable signs use the yellow triangle and lightning bolt with the words danger high voltage, keep out, authorised personnel only, and voltage-specific versions for 230, 400 and 11,000 volts, plus a fill-in "Danger ____ volts" sign where you write the voltage yourself. Print on A4 or A3, in portrait or landscape. The sign must match the supply: only use a voltage sign if it matches the supply behind it; if you are unsure, ask a qualified electrician, and use the general high voltage version.
Danger - high voltage sign
Sign text: "Danger / High voltage". PDF, 14 KB. A5, A4 or A3, portrait or landscape.
Buy a durable version
Rigid plastic, aluminium or self-adhesive high voltage signs, ready to put up. The pictures are our own free designs, not the Amazon products.
Rigid danger high voltage sign
View on Amazon - Rigid danger high voltage sign (affiliate link, opens in a new tab)
Self-adhesive high voltage labels
View on Amazon - Self-adhesive high voltage labels (affiliate link, opens in a new tab)
Weatherproof aluminium high voltage sign
View on Amazon - Weatherproof aluminium high voltage sign (affiliate link, opens in a new tab)
Also useful: A4 laminating pouches (to protect a printed sign) on Amazon (affiliate link, opens in a new tab)
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Choose your wording
7 versions. Each one downloads as a PDF in A5, A4 or A3, portrait or landscape.
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High voltage - keep out
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High voltage - authorised personnel only
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Danger - 230 volts
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Danger - 400 volts
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Danger - 11,000 volts
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Danger - ___ volts (fill in)
Download all 7 signs
Every wording, size and orientation in one ZIP file, 593 KB.
Print tips
- Print at "actual size" or 100%, not "fit to page", so the margins stay even.
- Use thicker paper or card (160gsm or more) if the sign will be handled.
- For outdoor or long-term use, laminate it or buy a rigid version.
Where to use it
- Substations, transformer cabinets and switch rooms
- Supply cupboards and meter rooms
- Farm and site fences near overhead or underground supplies
- Site distribution units and generators
- Plant enclosures and control cabinets
Questions
Which voltage sign should I use?
The one that matches the supply, as stated by a qualified electrician or your supplier. If you are unsure, use the general danger high voltage sign.
Is a sign enough to keep people safe?
No. Live equipment needs to be properly enclosed, locked or fenced. The sign tells people why.
What is the difference between this page and electrical warning signs?
Electrical warning signs cover everyday electrical hazards such as panels and switch rooms. This page covers high voltage and voltage-specific signs.
What size should I print?
A3 for gates and fences where people approach from a distance, A4 for doors and cabinets.
Related signs
Electrical Warning Signs
Danger Signs
Keep Out Signs
Hazard Warning SignsWarning class. A yellow triangle with a black edge warns of a hazard. All construction signs