Water bath is a basic equipment that is used in almost every lab conducting temperature control experiments. Given the hectic schedule of lab personnel, the cleanliness of lab equipment tends to be overlooked, leading to possible Legionella contamination. The contamination risk of an equipment is highest where water is stored or recirculated in the critical temperature range of 20° – 45°C (peaking at 37°C).
Legionella pneumophilia and related bacteria are commonly found in very low numbers in natural water resources. A favorable temperature and presence of food supply will promote bacterial growth. This increases the risks of legionnaires disease, which is a potentially fatal form of pneumonia as well as less serious conditions such as Pontiac fever and Lochgolihead fever.
To reduce the risk of Legionella contamination, it is suggested to perform a clean-up for water baths monthly. A typicaly clean-up protocol may comprise of:
• Disinfect thermally by increase the temperature to 60°C and maintain for 30 minutes. Dispose water.
• Clean and descale bath
• Fill bath with deionized or distilled water
• Add biocide tablet or chlorine based on the recommended dosage. The manufacturer of the water baths should be consulted to identify suitable chemicals that are compatible with the equipment
Having a policy on the control of Legionella in laboratory equipment is ideal. Regular cleaning of water baths will keep lab personnel safe from legionnaires disease.
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Grant Instruments was founded in 1951. Being a pioneer in temperature control solutions, Grant has been a leading manufacturer of innovative lab equipment and data acquisition tools for the scientific, healthcare and industrial markets worldwide.