alert
area
attention
background
beware
black
caution
chemical
danger
dangerous
design
electromagnetic
energy
frequency
graphic
hazard
hazardous
high
icon
illustration
industrial
information
ionizing
isolated
label
microwave
non
nonionizing
notice
power
protection
radiation
radio
radioactive
restricted
rf
risk
safety
security
sign
signal
sticker
symbol
technology
triangle
warning
wireless
yellow
zone