alone

backroom

caucasian

chemistry

container

cylindric

dark

dirty

dressed

dressuniform

engineer

engineering

environment

equipment

factory

filtering

filters

filtration

glassvare

gloves

industrial

industry

jacket

laboratory

large

liquid

male

operator

pipe

pipeline

plastic

processing

protection

purification

room

routine

science

sink

something

sprays

stands

table

technology

unfold

uniform

water

worker

zinc