It is recommended that monitoring for legionella is carried out:
when there is evidence that the system has become contaminated
is a system is suspected of causing a case of legionellosis
when control levels for the system (i.e. temperature, biocide, regular usage) are not being consistently achieved
in instances where the control regime for a hot water system involves maintaining a lower temperature, to save energy, in conjunction with use of a biocide.
Testing of samples for legionella can only be performed in laboratories accredited to BS EN ISO/IEC 17025:2005 with current ISO standard methods for the detection and enumeration of legionellae included within their scope of accreditation.
These methods can be for detection and enumeration of legionella by culture for viable cells or by a validated and accredited qPCR method.
Watertec’s analytical services provider holds the appropriate UKAS accreditation.