Science & Environment
Chlorine Contact Time CT Value Disinfection Calculator
Calculate the CT value used to evaluate chlorine disinfection performance in water treatment.
Your inputs
Change any value to update the result instantly.
CT value
45 mg·min/L
Required CT
30 mg·min/L
Margin over requirement
15 mg·min/L
Meets disinfection target
1 Yes
Formula and working
CT = residual chlorine concentration (mg/L) × contact time (min)
- 1
Collect the inputs
Residual chlorine concentration = 1.5 mg/L; Contact time = 30 min; Required CT for target log inactivation = 30 mg·min/L
- 2
Apply the formula
CT = residual chlorine concentration (mg/L) × contact time (min)
- 3
Result
CT value = 45 mg·min/L
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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