What is the best way to ensure the proper concentration of chemical sanitizers?

Several things can influence the effectiveness of chemical sanitizers. The most important are concentration, temperature, contact time, water hardness, and pH. The chemical sanitizer that your operation uses should have test-strips provided by the manufacturer. Follow the instructions according to the manufacturer's recommendation to get the correct concentration for that sanitizing agent. The manufacturer should also provide guidelines for temperature, contact time, water hardness, and pH. These guidelines should be followed closely.