1.1 This guide covers appropriate responses for employers, building owners and operators, facility managers, health and safety professionals, public health authorities, and others: (1) to a concern that a water system may be contaminated with the bacterium known as legionella (see 6.1); and (2) to the identification of one or more cases of Legionnaires' disease or Pontiac fever (see 6.3 - 6.5). Comprehensive and explicit recommendations to limit legionella multiplication in water systems, disinfect potential sources of human exposure to legionella, and prevent health-care associated infections are beyond this guide's scope.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. See 7.3 and 8.5 for specific hazard statements.