Water Treatment
ASHRAE Technical Committee 3.6

Scope of TC 3.6

TC 3.6 is concerned with water treatment for building water systems including scale, corrosion and microbiological control (except sewage drainage systems) and the impacts of water treatment on building operations, maintenance, sustainability, energy efficiency, human health, and water resource conservation.


The ASHRAE Handbook is published in a series of four volumes, one of which is revised each year, ensuring that no volume is older than four years.

TC 3.6 is responsible for the following chapter in the HVAC APPLICATIONS handbook:

Water Treatment

This chapter covers the fundamentals of water treatment. It provides guidance on the treatment of water and water-based fluids used in heating, air-conditioning, refrigeration, and process systems, with a focus on the control of corrosion, scale, fouling, and biological growth. Proper treatment improves the performance and energy efficiency of these systems while helping to protect human health and safety. Water treatment also extends the life of equipment in both open- and closed-loop systems. In addition, water treatment can help conserve water resources as well as enable the use of alternative sources of water. All of these benefits help to promote a healthier, more sustainable environment.

The ASHRAE HVAC APPLICATIONS HANDBOOK may be purchased from the on-line bookstore by clicking on the highlighted text.

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Technical Committees are responsible for identifying research topics, proposing research projects, selecting bidders, and monitoring research projects funded by ASHRAE. Information about their specific research program is discussed at each TC meeting and at the TC’s Research Subcommittee meeting.

Click here for the TC 3.6 Long Range Research Plan.


ASHRAE writes standards for the purpose of establishing consensus for: 1) methods of test for use in commerce and 2) performance criteria for use as facilitators with which to guide the industry. ASHRAE publishes the following three types of voluntary consensus standards: Method of Measurement or Test (MOT), Standard Design and Standard Practice. ASHRAE does not write rating standards unless a suitable rating standard will not otherwise be available. ASHRAE is accredited by the American National Standards Institute (ANSI) and follows ANSI's requirements for due process and standards development. Standards may be purchased at the ASHRAE Bookstore.

ASHRAE Guideline 12: Minimizing the Risk of Legionellosis Associated With Building Water Systems

ANSI/ASHRAE Standard 188: Legionellosis: Risk Management for Building Water Systems

Other Activities

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Include other activities, such as MTG involvement, into this section.


ASHRAE Technical FAQs are provided as a service to ASHRAE members, users of ASHRAE publications, and the general public. While every effort has been made to ensure their accuracy and reliability, they are advisory and provided for informational purposes only, and in many cases represent only one person’s view. They are not intended and should not be relied on as an official statement of ASHRAE. Technical questions not addressed may be submitted to the ASHRAE Technical Services department at tse@ashrae.net.

How does ASHRAE recommend that cooling towers be cleaned to avoid Legionellosis? (18)

Working Group

The following link can be used to access the TC3.6 working group: