When it comes to safety signage, let’s make one thing clear right from the start: Signs are not to serve as substitutes for safe conditions. For example, signs are never intended to take the place of machine safeguarding. Nor should you settle on using a sign to caution about hazards that could have been abated so that no sign would have been needed to begin with.

With all uses of signs, keep focused on the ultimate goal: to convey very specific information in unambiguous terms. Be 100 percent sure that the words, pictures, diagrams, schematics, symbols or codes are fully comprehensible to everyone who needs to gain the knowledge intended to be imparted by the sign. The caution, instructions or other category of message should be clear without the need for consulting another person. However, all employees must know that they can — and are absolutely expected to — contact the relevant personnel if they do not totally understand the meaning of a sign.

What’s the hazard?

Where warnings are involved, the sign should indicate the type and degree of hazards. There are many cases where there is a need to include the hazards associated with misuse and improper handling. There must be no doubt as to what the hazard is and why it is a hazard.

For example, a simple written communication (even when accurate) indicating that there should be no smoking or open flames near an area or product is generally insufficient. The message should convey what the adverse result can be. I do not suggest that the addition of the words “vapor ignition” is, in itself, satisfactory. The word “explosion” ought to be a part of the warning. In a related vein, I recall a fatality that occurred in a permit-required space. A sign near the entrance to a large pipe indicated words at least very similar to “WARNING: ARGON PURGE.” Those words do not suitably command the attention of the reader. The warning should have clearly conveyed the message that there was a grave danger of oxygen deficiency.

Logical order

When several bits of information are needed on a sign, there is a logical, preferred order of message components. They are generally best communicated when laid out from top to bottom; occasionally a left-to-right orientation is appropriate. The signal word (such as “Danger”) should be first. Then, wording should describe what actions to take or to avoid. Next is the hazard description, followed by the description of adverse health and safety consequences (injuries or illnesses) to be encountered if warnings and/or instructions are not heeded. In some cases, emergency contact information, including a telephone number, is appropriate.

Additional format factors relate to how easily signs can be read, and how quickly intended messages can be understood. This is most important when there are several words on a sign. Clarity is a must. Except for the header (all capital letters), it is best to use a proper mix of upper and lower case letters (not all capitals). Every effort should be made to include key word clusters (groups of words that should be absorbed together to convey a single idea) on one line; when such clusters are split, a fast reading can too easily result in misinterpretation. When there are many lines (especially with sentences), justifying to the left (a flush left alignment, a consistent left margin) is recommended, as opposed to centering. However, justifying to the right is not recommended; instead, a “rag” right seems to complete a more visually comfortable set-up, even if it provides less of a neat look.

Location, location, location

The proper posting of exit signs should be well understood. This subject has been written about and discussed, again and again, and its importance cannot be overstated. There is no excuse for inadequate signage relating to emergency escape. Yet, in an all-too-common scenario, exit signs at the rear of, for instance, a supermarket, warehouse or large room in an industrial setting are flat against a wall and cannot be discerned from even a few feet to the side. (Such poor sign location often relates to extinguishers, as well.) This type of hazard is often exacerbated by a rack or a recessed position.

There are times that arrows are needed. There is also a requirement for “NOT AN EXIT” signs, or signs indicating the actual character of the opening, such as “BOILER ROOM,” “SUPPLY CLOSET,” etc. This is necessary if a door, archway or similar opening could reasonably be mistaken for an exit, even though the evacuee would be entering a dead-end or otherwise hazardous area.

Signs on doors

Problems can be needlessly created when a sign is placed on a door, and not supplemented by a duplicate sign above (or very near) the door. Doors may be left open, at an angle that precludes a view of the sign when walking toward the opening. If the door is opened into the room or space to be entered, sometimes the sign is only spotted when the person has already passed through the door frame; when the door is opened far beyond 90 degrees, the person may walk by the sign and miss it entirely. If the door is opened away from the room or space to be entered (toward the would-be reader), there is an even greater chance that the sign will go unnoticed; it may now be behind (on the other side of) the door surface that remains in view.

If there was an unseen exit sign on the door, an evacuee may well waste time going to an exit that is farther away. If an unseen sign on the door indicated that it was not an exit, an evacuee may have assumed the opposite and entered an area that did not provide escape. In this scenario, the evacuee may have even gone into a space that has added hazards, especially in respect to fire. The unseen sign may have been unrelated to egress decisions; rather, it may have been posted to warn about particular hazards (and/or the need for personal protective equipment) in the space beyond the door.

Other sign considerations

There are other considerations for sign design and placement. If a sign is susceptible to chemical splash, excessive heat or cold, or the adverse effects of various elements of weather, there may well be a need to use special materials, laminate the sign, or otherwise assure that the message will be easily readable and that the sign will remain in good condition.

Regardless of the color scheme of the sign, be certain that it contrasts well with the wall (or other surface) on which it is posted. Place signs logistically, at appropriate heights and angles.

I have witnessed numerous instances of signs that were not adequately conspicuous, and other cases where, although the presence of a sign was fairly evident, reading the words and/or symbols was quite difficult. Avoid these situations by posting well-designed safety signs in proper locations.


Regarding mounted evacuation route floor plans (diagrams), it is particularly important that this sort of sign be unambiguous and uncluttered. Use simple symbols and distinct colors to indicate the locations of exits, extinguishers and manual alarms. Use easy-to-read print, and an easy-to-discern symbol, for the vital YOU ARE HERE designation.

Be certain that the plan is positioned (such as on the proper wall) so as to provide the correct orientation for the reader directly in front of it. This principle is often breached and could lead to a tragic misunderstanding. Even if the plan is perfectly drawn, the information is crystal clear and the orientation is accurate, the posting cannot be used in lieu of evacuation training. Further, the floor plan is not a substitute for exit, extinguisher and manual alarm signs.

SIDEBAR 2: Don’t be left in the dark

For an excellent supplementary system, utilize photoluminescent (glow-in-the-dark) signs, arrows and strips, especially beneath the potential blanket of smoke. Highlight doors, including frames, bars, knobs and levers, paths, steps, landings, handrails and newel posts. Mark obstacles, such as standpipes, hose cabinets and restricted height areas.