The OSHA Technical Manual on Legionnaires’ Disease from 1996 provides guidance to industrial hygienists for assessing work sites for potential risks associated with Legionnaires’ disease. The manual covers topics like disease recognition, investigation procedures to identify probable water sources, and control strategies aimed at managing the risks associated with the disease. The content within the manual is structured into different sections covering an introduction to Legionnaires’ disease, disease recognition, source identification, investigation protocol, controls, and a bibliography. It also contains appendices on employee awareness programs, physical survey and water sampling protocol, and water sampling guidelines. Read the full report here
In the EPA’s 1999 Legionella: Human Health Criteria Document, the agency underscores the significance of Legionella, bacteria commonly found in warm, man-made water systems. This bacterium can lead to diseases such as Legionnaires’ disease, a severe pneumonia-type illness, and the less severe Pontiac Fever. Primary exposure comes from inhaling contaminated water aerosols, with heightened risks in susceptible populations like the elderly and immunocompromised. The document stresses the challenges in delineating a clear correlation between exposure dose and disease due to bacterial strain diversity and individual susceptibilities. It highlights the need for robust water system management, including temperature control and disinfection. The EPA advocates for more research and the exploration of advanced control measures, such as UV light treatment, to curb Legionella proliferation. Read the full report here
The 1999 and 2001 EPA documents provided an overview of Legionnaires’ disease and prevention strategy, agreeing with the OSHA document and other publications that building water management was needed to reduce risk: “Because there is little if any person-to-person transmission of Legionella and no vaccine is available to prevent infection, risk minimization efforts are focused on breaking the chain of transmission between environmental sources of Legionella and human hosts. …For hospitals and other health care settings, regular environmental surveys of both hot water systems and distal sites should be conducted; some health departments have issued mandates for such testing.” Read the full report here.
In the 2016 report titled “Technologies for Legionella Control in Premise Plumbing Systems,” the US EPA reviews existing scientific literature to evaluate various technologies aimed at controlling Legionella in building plumbing systems. Legionella, the bacterium causing diseases like Legionnaires’ disease, thrives in warm water environments within many buildings. The document highlights multiple methods to combat its growth and spread. These methods encompass thermal treatments, disinfection techniques such as chlorination and ultraviolet light, as well as advanced filtration systems. The report emphasizes the efficacy, advantages, and drawbacks of each technology, providing guidance for best practices. As the threat of Legionella remains significant, especially in large facilities, the EPA stresses the importance of continuous research, system monitoring, and technology advancements to ensure public health. Read the full report here