Control of Legionella bacteria in the Public Works and Government Services Canada real property portfolio

The health and safety of occupants and users of federal buildings is the top priority of Public Works and Government Services Canada (PWGSC).

PWGSC has taken a leadership role as a custodian department to put in place strong processes to prevent the occurrence of Legionnaires' disease in buildings managed by the department or its service providers.

Legionnaires' disease is a form of respiratory infection and is not contagious. The primary route of transmission is through the inhalation of water vapour or mists that have been contaminated with Legionella bacteria. Legionella bacteria can grow in building water systems that have the following conditions favourable to their growth:

  • a temperature range between 20 and 50°C;
  • water stagnation; and
  • a lack of system cleanliness.

The key to preventing outbreaks of Legionnaires' disease is to control Legionella bacterial growth in water systems through preventive maintenance.

Since 1986, PWGSC has been proactively operating and maintaining its buildings to ensure that they comply with codes, standards, and other requirements related to health and safety. In addition, property maintenance projects related to health and safety have been delivered and funded on a priority basis.

Following the outbreak of Legionnaires' disease in Quebec City in summer 2012, and the discovery that a cooling tower was the source, the Province of Quebec developed new regulations for the operation and maintenance of cooling towers. Although no Crown-owned or PWGSC-operated buildings were implicated in the outbreak, the department was proactive in reviewing its guidelines for controlling Legionella and issued a new standard, MD 15161—Control of Legionella in Mechanical Systems.

Key features of the Quebec regulations include the registration of all cooling towers in the province, and the creation of a Legionella control plan for each tower that must be certified by a licensed professional engineer. Meanwhile, the scope of the new PWGSC Legionella standard covers not only cooling towers but all Legionella-susceptible systems.

In buildings leased by PWGSC, the lease agreements stipulate that the building must be operated and maintained in compliance with all applicable federal, provincial/territorial, municipal, and regional laws, acts, regulations, and codes. This includes compliance with American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) standards related to the maintenance of heating and cooling systems.

The department also works closely with regional health authorities when there is an outbreak of Legionnaires' disease to ensure that PWGSC buildings remain safe.

The following policies and practices relating to the prevention and control of bacterial growth in PWGSC-owned buildings are in place, based on federal and ASHRAE requirements:

  • The Real Property Services Facility Maintenance Policy requires preventive maintenance that includes inspection, testing, and cleaning of mechanical systems.
  • The PWGSC Legionella standard, Control of Legionella in Mechanical Systems, provides requirements for proper design, maintenance, operation, and bacterial testing to prevent the growth of Legionella bacteria.

Timely notification will be provided to the appropriate stakeholders should any system test above the allowable threshold limits for Legionella bacteria.

More information on Legionnaires' disease can be found on the Health Canada website.

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