ban
basin
building
caveat
chemical
chemical symbol
chemistry
chlorination
chlorine
chlorine clorum
clean
clean water
cleanliness
clear
color chart
danger
disinfection
door
element
endanger
entrance
equipment
forbidden
german
health
inspection
instructed
maintenance
no person
periodic
persons
ph
ph corrector
pool
pump
purity
quality
safety
science
security
sign
signal
signalise
swimming
symbol
system
text
treatment
warning
water