What is an advantage of using chlorine gas to disinfect drinking water supplies?
A) It provides residual protection against pathogens.
B) It gives the water a fresh taste.
C) Residual chlorine in water helps to whiten teeth.
D) Excess chlorine is absorbed in our bodies as a mineral supplement.
Question 2
Why are there few odors emanating from a properly managed composting toilet?
A) Tight seals prevent the escape of odors.
B) Odors are absorbed by a layer of water.
C) Decomposition is aerobic.
D) The ventilation system steers odors through a carbon filter.
Water Properties
Water Hole
Turn on water
Waves in Deep and Shallow Water
A typical purified water system
Most Americans obtain their drinking water from a community water system