Electrical room signs: what goes on the door, and what goes inside
A checklist of electrical room signs: authorized personnel only and keep out signs for the door, keep clear signs, arc flash lamacoids and panel ID inside.
An electrical room is one of the few spaces in a building where the signs matter to three different audiences. The electrician needs to know what's in there and how hot it is. Everyone else needs to know to stay out. And the inspector needs to see that you've thought about both.
Here's a working checklist of electrical room signs, split into what goes on the door and what goes inside.
On the door
The door is where you stop people who shouldn't be inside. Most electrical room doors carry two or three signs.
1. Room identification
"ELECTRICAL ROOM" or the room's name from the drawings, such as "MAIN ELECTRICAL ROOM" or "ELECTRICAL ROOM 2B." This helps firefighters, facility staff and contractors find the right door fast. Match the name on the single-line diagram and the panel schedule.
2. Access restriction
"AUTHORIZED PERSONNEL ONLY" is the standard. "KEEP OUT" is blunter and works well for outdoor enclosures, rooftop gear and service yards.
| Wording | Signal word | Best for |
|---|---|---|
| AUTHORIZED PERSONNEL ONLY | CAUTION or NOTICE | Interior electrical rooms, telecom rooms, mechanical rooms |
| ELECTRICAL ROOM / AUTHORIZED PERSONNEL ONLY | CAUTION | Combining ID and access on one plate |
| KEEP OUT | DANGER or WARNING | Outdoor enclosures, fenced gear, rooftop equipment |
| HIGH VOLTAGE / KEEP OUT | DANGER | Rooms and vaults with live parts above low voltage |
Use CAUTION or DANGER when the reason for keeping people out is a real injury hazard. NOTICE fits access rules that aren't about a hazard. See Danger vs warning vs caution signs if you're deciding between them.
3. Voltage hazard
If the room holds medium or high voltage switchgear or transformers, put a DANGER sign on the door that states the voltage. "DANGER / 27,600 VOLTS / KEEP OUT" tells an approaching worker exactly what's behind the door. More on this in the high voltage signs guide.
Inside the room
Keep clear signs
Electrical rooms have a way of becoming storage rooms. Boxes of paper, spare ceiling tiles, a broken chair. The Canadian Electrical Code (CSA C22.1) requires working space to be kept clear around electrical equipment so it can be operated and serviced safely. The dimensions depend on the equipment and voltage, so check the working-space rules in the current edition of the CEC for your installation.
A keep clear sign mounted on or beside the panel, sometimes paired with floor striping, reminds everyone that the space in front of the gear isn't free real estate.
Arc flash lamacoids
Equipment that may be worked on while energized needs its arc flash hazard marked. The CEC requires marking, and CSA Z462 sets out what an arc flash label should include once you have an arc flash study, such as the nominal voltage, arc flash boundary and either incident energy or PPE category. The study data comes from your engineer. We engrave it.
Engraved arc flash lamacoids hold up better than printed stickers on gear that gets opened, wiped down and worked around for years. See arc flash labels in Canada for the details, and the arc flash labels page for layouts.
Shock and electrical hazard signs
For equipment with exposed or accessible live parts, "WARNING / ELECTRICAL HAZARD" or "WARNING / SHOCK HAZARD" signs on covers and doors are common. They're especially useful on gear that isn't covered by an arc flash label, like control panels and small disconnects.
Panel and equipment ID
Every panel, disconnect, transformer and MCC in the room should be identified: what it is, what feeds it, what it feeds. In Ontario, circuit identification in panels has been getting more attention from inspectors, so it's worth doing properly. Engraved lamacoids for panel, breaker and equipment ID are our main line at llamacoids.ca.
Quick checklist
- Room ID sign on the door, matching the drawings
- AUTHORIZED PERSONNEL ONLY or KEEP OUT sign on the door
- DANGER sign with voltage on the door if medium or high voltage gear is inside
- Keep clear signs at panels and switchgear
- Arc flash lamacoids on equipment covered by your arc flash study
- Shock or electrical hazard signs on other equipment with live parts
- ID lamacoids on every panel, disconnect, transformer and MCC
Mounting and material
- Doors: screws or rivets for steel doors, adhesive plus screws for wood or painted surfaces that get cleaned often.
- Equipment: adhesive works on clean, flat, indoor surfaces. Drill holes if the gear runs hot or gets washed down.
- Height: eye level on the door, on the latch side if the hinge side swings out of view.
Engraved phenolic is non-conductive and the text is cut into the plate, so it won't peel or wear off with cleaning. That's why it's the standard in electrical rooms.
Getting it done in one order
Send us the room list and the gear list and we'll quote the door signs, keep clear signs, arc flash lamacoids and panel ID together. Same day on most orders, out of Burlington. Browse the electrical room signs page, mock one up in the sign builder, or order ready-made plates from the shop.
Build your sign and order online or call 289-275-9572.
FAQ
Frequently asked questions
What sign goes on an electrical room door?
Most electrical room doors carry an identification sign (ELECTRICAL ROOM), an access sign (AUTHORIZED PERSONNEL ONLY or KEEP OUT), and a hazard sign with the voltage where live parts over low voltage are present, such as DANGER HIGH VOLTAGE. Your site standard and the authority having jurisdiction decide what is required.
Do I need a keep clear sign in front of electrical panels?
The Canadian Electrical Code requires working space to be kept clear around electrical equipment. A keep clear sign or floor marking is a common way to stop that space from turning into storage. Check the working-space rules in the current edition of the CEC for the dimensions that apply to your equipment.
Should an authorized personnel only sign use CAUTION or NOTICE?
Either is common. Use CAUTION or DANGER when the reason for restricting entry is an injury hazard, like live electrical equipment. NOTICE is better suited to access policy with no direct hazard. Consistency across the site matters more than the specific choice.
Can you make the panel ID tags and the door signs together?
Yes. Llamacoids makes both the safety signs and the panel, breaker and equipment ID lamacoids, so an electrical room can be done in one order with same-day turnaround on most jobs.
