alert
arrow
attention
background
beware
black
careful
caution
current
danger
dangerous
death
electric
electrical
electricity
electrocution
energy
fence
forbidden
hazard
high
icon
industrial
industry
information
lightning
line
metal
notice
power
precaution
protect
protection
risk
safety
security
shock
sign
signal
substation
supply
symbol
technology
text
transformer
triangle
volt
voltage
warning
yellow