biological
black
bomb
caution
chemical
danger
design
equipment
filter
fire
flame
gas
grenade
hazard
helmet
icon
industry
infection
injury
isolated
lighting
line
mask
military
nuclear
outline
poison
pollution
protection
protective
radiation
radioactive
rain
respirator
safety
security
sign
signal
skeleton
skull
slip
slippery
symbol
thin
toxic
umbrella
warning
white