Issue link: https://hi.iaq.net/i/692160
18 DEVELOPING A LEGIONELLA WATER MANAGEMENT PROGRAM 5 CONTINGENCY RESPONSE EXAMPLES Even the most closely monitored systems will sometimes require adjustments, as shown in the following examples. You should be prepared to respond, even to unexpected problems, based on your knowledge of the building water systems and how Legionella grows and spreads. You may need to initiate a customized contingency response to gain control of a building water system. Contingency responses may involve several steps and often require follow up. A contingency response is always required when a case of Legionnaires' disease has been linked to a building and is also appropriate in other situations. Example 1—Biofilm growth in the fountain 1. During the annual review of the water management program, supervisor Anson Cho notes that Michelle and Jason performed six interim cleanings of the lobby fountain due to excessive biofilm growth in the past year. 2. Upon further review of the logs, he discovers that the biofilm growth was observed near the inner wall where incandescent lighting illuminates the water. Anson replaces the incandescent bulbs with LED bulbs and documents reduced growth after three months of inspections. 3. Anson decides to replace the incandescent bulbs with LED bulbs to prevent the lights from heating the water to a temperature that allows biofilm to grow. 4. After three months of routine inspections show that this corrective action reduces biofilm growth and eliminates the need for interim cleaning, Anson amends the water management program to specify use of only LED bulbs in the fountain and he informs the owner. Disclaimer: Example content is provided for illustrative purposes only and is not intended to be relevant to all buildings. Reference: ASHRAE 188: Legionellosis: Risk Management for Building Water Systems June 26, 2015. ASHRAE: Atlanta. www.ashrae.org