機器
air
air filter
airborne
auto
bacteria
carbon
clean
cleaner
cold
conditioning
conservation
disposable
distilled
dust
efficient
engine
environment
equipment
filter
filtration
health
healthy
heat
heater
household
mechanic
mechanical
mesh
metal
motor
natural
nature
part
particle
piece
pipe
pollution
purification
purifying
purity
relief
replacement
spare
spray
strainer
technique
technology
utilities
ventilating