Owners of cooling towers and/or evaporative coolers (cooling units) within New York State are required to develop a written maintenance program and plan in accordance with ANSI/ASHRAE Standard 188-2015, as per New York State Department of Health (NYSDOH) Protection Against Legionella regulations, effective July 6, 2016. A copy of this plan must be readily accessible at each facility at all times.

The Legionella Preventive Maintenance Plan (Plan) must contain the following provisions, at a minimum:

A description of the building cooling system and potential sources of contamination.

  • Owners must review unit specifications and identify potential sources of bacterial contamination into the HVAC system. Additionally, all potentially hazardous airborne discharge locations (such as building openings and air intakes) must be identified.

 A standard operating procedure for cleaning and disinfecting any tower that has been shut down for more than five consecutive days.

  • Owners of the majority of cooling units can meet this requirement by performing physical and chemical (using a USEPA-registered biocide) disinfection prior to the cooling season and performing routine chemical treatment while the cooling units are in operation (commonly from late April until October). The Plan shall also detail a schedule for periodic inspection.

A schedule and method for routine microbiological culture sampling and analysis.

  • Every 30 days while the cooling units are in operation, a live culture growth sample must be evaluated to assess the growth of aerobic bacterial populations.

A schedule for Legionella culture sampling and analysis.

  • Within 14 days of startup, and then every 90 days, water samples must be collected from each cooling unit and tested for the presence of Legionella The testing must be performed by a laboratory with a certified Environmental Legionella Isolation Techniques Evaluation (ELITE) Program. Additionally, samples must be collected immediately if there is a prolonged power failure in the building served by the unit, or failure to perform routine chemical disinfection for a period long enough to allow bacterial growth.

A detailed emergency response procedure.

  • The Plan shall detail specific steps to be followed by all building staff and occupants if there are known or suspected concentrations of Legionella bacteria within one or more cooling units within a facility. A procedure for emergency cleaning and/or disinfection, and subsequent laboratory analysis shall be outlined within the Plan.

Procedures for temporary or permanent shutdown of a cooling unit.

  • The Plan shall detail procedures followed to treat and remove water from the cooling unit and all associated components at the end of the cooling season or when decommissioning a given unit.

 For more information on how Walden can help you prepare a Legionella Preventive Maintenance Plan, please give us a call at 516-624-7200.