Guidelines For Dental Offices During a Boil Water Advisory

NOTE: These guidelines have been designed for generic use in a boil water advisory. Please contact your Health Unit for information regarding the particular circumstances of a specific boil water event.

The guidelines below are provided to dental offices further to the boil water advisory issued by the Medical officer of health.

During a Boil Water Advisory

Under the Boil Water Advisory it is unsafe to drink or use tap water to brush teeth, gargle or rinse dentures. Under these precautions, tap water should not be used for dental treatments. Dental offices are strongly advised to follow the guidelines below:

Before Treatment:

• Explain to all patients the impact of the BWA on dental care and indicate what procedures your office is following
• Warn your patients before treatment that they are at greater risk for water borne illness if they are immunocompromised and allow them to reschedule appointments if desired.
• Reschedule appointments for known immunocompromised patients, such as HIV-positive individuals, chemotherapy and transplant patients, and congenitally immunocompromised individuals
• Reinforce that patients use only boiled or commercially bottled water for toothbrushing or other dental care in their own homes

During Dental Procedures:

• Use only boiled or bottled water for patients to drink and rinse in your office.
• Ensure that any ice chips are made from disinfected water sources.
• Turn off the water supply to high-speed handpieces. Using disinfected water, flow water out of a bulb syringe when using high-speed handpieces, or
• Run your high/low speed turbines dry and use a hand syringe of boiled or bottled water for cooling and rinsing
• Use a hand syringe of boiled or bottled water in place of the air/water syringe
• In the event of contamination caused by cryptosporidium, and where bacterial contamination has definitely been ruled out, install a commercial filter system that removes particles one micrometer or less in diameter. Filters that provide the greatest assurance of Cryptosporidium/Giardia removal include those that use reverse osmosis, those labelled as "Absolute" one micrometer filters, or those certified to remove protozoan parasites including Cryptosporidium/ Giardia. As with all filters, follow manufacturerer's instructions for filter use and replacement.

Other:

• Ensure thorough handwashing by all staff using disinfected water
• Post notices by all sinks advising not to drink the tap water
• Post notices by all sinks and in washroom areas reinforcing the importance of proper handwashing technique. Provide disinfected water or sanitizers for this purpose.
• Exclude all employees with diarrheal illness from work following standard rules of exclusion

Upon Rescinding a Boil Water Advisory

• Re-start and flush any water-using fixture or piece of equipment in accordance with the manufacturer's specifications. This may vary from fixture to fixture. Consult your facilities engineer and/or the manufacturer when re-starting the equipment
• Managers of large buildings with water-holding reservoirs should consult with their facility engineer and health department about draining the reservoir
• Run cold water faucets for one minute before using the water
• Run drinking fountains for one minute before using the water

Adapted from Guidelines contained in the Protocol for the Investigation and Control of Cryptosporidium and Giardia Waterborne Outbreaks (1997) and Cryptosporidium and Water: A Public Health Handbook (1997).