We all know what chlorine is. It’s a gas used to disinfect our water. It’s a carcinogen. The only good thing we can say about it is that if you pour yourself a glass of water and leave the glass open on the bench for half an hour, the chlorine gas, previously trapped inside the pipes supplying your home, will ‘outgas’ and leave the water.
When the word ‘Chloramine’ is mentioned I’m usually confronted with a blank stare. Most people take the easy path and assume it’s like chlorine. It’s not, and I’ve taken the liberty of quoting directly from the EPA website to hellp you out.
Chloramines in Drinking Water
Chloramines are disinfectants used to treat drinking water. Chloramines are most commonly formed when ammonia is added to chlorine to treat drinking water. The typical purpose of chloramines is to provide longer-lasting water treatment as the water moves through pipes to consumers. This type of disinfection is known as secondary disinfection. Chloramines have been used by water utilities for almost 90 years, and their use is closely regulated. More than one in five Americans uses drinking water treated with chloramines. Water that contains chloramines and meets EPA regulatory standards is safe to use for drinking, cooking, bathing and other household uses.
Many utilities use chlorine as their secondary disinfectant; however, in recent years, some of them changed their secondary disinfectant to chloramines to meet disinfection byproduct regulations. In order to address questions that have been raised by consumers about this switch, EPA scientists and experts have answered 29 of the most frequently asked questions about chloramines. We have also worked with a risk communication expert to help us organize complex information and make it easier for us to express current knowledge.
- What are chloramines? PDF (1p, 26K)
- How long has monochloramine been used as a drinking water disinfectant? How is monochloramine typically used? How many people/water utilities use monochloramine? PDF (1p, 27K)
- Why is drinking water disinfected? What is the difference between primary and secondary disinfection? How is monochloramine used in a treatment plant? PDF (1p, 28K)
- What disinfectants are available for drinking water? PDF (1p, 19K)
- How effective is monochloramine vs. chlorine as a primary disinfectant? PDF (1p, 23K)
- How effective is monochloramine vs. chlorine as a secondary disinfectant? PDF (1p, 25K)
Water systems, disinfection byproducts, and the use of monochloramine
- Why are disinfection byproducts a public health concern? PDF (1p, 23K)
- How does EPA regulate disinfection byproducts (DBPs)? PDF (1p, 27K)
- How do the kinds and concentrations of disinfection byproducts formed by monochloramine compare to those formed by chlorine? PDF (1p, 25K)
- Why are water utilities switching to monochloramine? PDF (1p, 23K)
- Other than chlorine and monochloramine, what options could water utilities consider to control the levels of disinfection byproducts? PDF (1p, 23K)
- Does EPA require water utilities to use monochloramine? Who approves the decision for a water utility to use monochloramine? PDF (1p, 22K)
- What assistance does EPA provide to water utilities that are considering a switch from chlorine to monochloramine? PDF (1p, 24K)