I can superexclusively document (and you can’t) that warning labels in a brand-new $750,000 ladder truck are typeset in Arial (also, confusingly, Helvetica and Futura).
Tactile signage in ladder truck
Additionally, this warning sign (yes, it really is located above an A[(]E[)]RIAL INLET!) is somehow typeset in three-dimensional, tactile Avant Garde Gothic and Helvetica Condensed, as though some ill-defined category of blind firefighter were expected to read it at a three-alarm blaze.