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What to do when your municipal water supplier issues a "boil water advisory"

glass of water Can we dialyze patients during a boil water advisory (BWA)?

Yes, if the water treatment components in use are sufficient to remove or destroy bacteria, Reverse Osmosis (RO) will protect the product water from having microbial contamination. Deionization (DI) unit does not remove or destroy bacteria, so if DI is being used as the main water treatment (rather than RO), you will need a submicron or endotoxin/ultrafilter downstream of the DI unit. If an ultraviolet (UV) irradiator is used, the filter should be located after the UV irradiator. Close monitoring of the resistivity of the product water will be needed to detect any decrease in quality. Also consider weekly microbial assessment of the product water during the BWA.

Keep in close contact with the municipal water supplier because they may choose to "shock" treat (hyperchlorinate) their distribution system to bring it back into compliance with the acceptable standards for drinking water. If the city "shocks" their water system, you may see chlorine/chloramine break through. Review your testing procedures with staff and alert them to be vigilant for potential break through so that patients will be protected from exposure to chlorine/chloramine.

BWA basics

What is a "boil water advisory?"

A boil water advisory (BWA) is issued to protect the community from waterborne infectious agents. A BWA is issued only after careful consideration among representatives from public health, regulatory agencies, and municipal departments after positive tests (e.g., positive samples for fecal coliforms, changes in turbidity measurements) or line breaks.

What should I do when under a BWA?

For personal use, create a supply of water for cooking, drinking, and tooth brushing by bringing water to a rolling boil for one minute. Timing starts when the water starts to bubble. Cool the water then place in clean containers for use or refrigerate.

Hot (not boiled) soapy water can be used for dishwashing and kitchen/bathroom surface cleaning. As a precaution, add one tablespoon of bleach per gallon. Laundry water does not need to be treated. Unless specifically listed, water for showering does not need to be treated.

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