STS Professional’s Dental Unit H2O Line Testing Kit is assembled for the Australian Dental Association's Guidelines for Infection Control 5th Edition.
Page 33 states, “It is good practice to test microbial levels in water from dental unit waterlines on a regular basis, for example six-monthly or annually”.
This kit includes 5 x Millipore microbiological HPC samplers for DIY testing and more details and instructions for use are found enclosed.
Current expiry of stock is FEB 2025.
Millipore Samplers simplify routine microbiological analysis of liquids for bioburden levels of bacteria. This product eliminates the cumbersome and expensive hardware and materials associated with traditional testing techniques.
A Sampler consists of a plastic dip test handle with a 0.45 µm Millipore filter, an absorbent pad which contains the dehydrated nutrient medium for recovery of specific organisms and an outer plastic sheath which can be filled with the sample liquid of choice. Samplers are suitable for testing high purity and environmental waters.
Once samples of water have been taken the HPC Samplers can be incubated for 48 hours. Alternatively, HPC Samplers can be left at room temperature for 7 days to achieve results. Colonies of growth can then be counted and estimated using the Comparison Chart provided.
For chlorinated water, obtain sterile sample bottles containing sodium thiosulfate to neutralise the residual chlorine. The STS Professional 5 pack of pre-dosed sodium thiosulfate sample bottles can be purchased here.
If the dental unit water line (DUWL) is sanitised with a chemical sanitant (peroxide, chlorhexidine gluconate based products, etc.), ask the manufacturer of the DUWL or sanitant supplier to recommend a suitable neutraliser. Neutralisers are necessary because disinfectants used to clean DUWLs may leave residuals that can inhibit recovery of microorganisms. The micro-organisms may not be killed but may be inhibited from replicating on media. This may lead you to conclude that since no colonies formed, the water is of good quality, when in fact the colonies did not form due to the bacteriostatic effect of the chemicals in the water.