alert
area
atom
background
caution
danger
electric
electricity
electromagnetic
environment
equipment
frequency
hazard
health
heat
high
hot
icon
industrial
ionizing
label
lowfrequency
medical
microwave
nonionizing
notice
nuclear
oven
pictogram
plutonium
protection
radiation
radio
radioactivity
ray
restricted
risk
risky
safety
security
sign
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sticker
symbol
technology
uranium
warning
wave
zone