Use capital letters for the first letter of the first
word and small letters for the rest.
Use appropriate warning words. These can be in capital letters, if you prefer. For example:
Danger (or DANGER) – to warn of a
definite hazard.
Caution (or CAUTION) – to warn of a potential hazard.
The lettering styles (fonts) most recommended are sanserif, bold or regular face. Examples include: Arial, Helvetica, Folio Medium, Futura, Univers, or equivalent.
Limit one message to a sign. To convey more than one message, use separate signs, as shown below. For example, if hearing protectors and safety glasses are required, use two separate signs, one for hearing protection, and another for eye protection.