The use of hard hats for construction workers started in 1931 at the Hoover Dam site in Nevada.
Typical hat colors are:
white | supervision, architects, supervising engineers |
yellow | construction workers |
green | first aid, safety or emergency team |
blue | direct employees, or emergency team |
orange | contractors |
white | supervision, architects, supervising engineers |
red | foreman, head-workman, site foreman |
orange | workers for enforced concrete, steel rod |
yellow | construction workers, masons |
green | carpenters, timbermans, ring builders, some times security personnel |
blue | some times craftsmen, handcrafter |