This is a legacy version of the WELL Building Standard. Please check the latest version here.

Public water additives

Sometimes, chemicals are intentionally added to water supplies. For example, chlorine or chloramine may be added to water to act as disinfectants, and fluoride may be added to prevent tooth decay. Although the addition of small amounts of these chemicals is beneficial for public health and safety, excessive exposure can lead to adverse effects, including fluorosis (aesthetic mottling of the teeth), stomach discomfort and eye and skin irritation. In addition, the use of chlorine can lead to the formation of disinfectant byproducts (DBPs), such as trihalomethanes (THMs) and haloacetic acids (HAAs), which have been linked to cancer and kidney damage.

Part 1: Disinfectants

All water being delivered to the project area for human consumption (at least one water dispenser per project) and showers/baths meets the following limits:

a.42 Residual chlorine less than 0.6 mg/L.
b.54 Residual chloramine less than 4 mg/L.
Part 2: Disinfectant Byproducts

All water being delivered to the project area for human consumption (at least one water dispenser per project) meets the following limits:

a.54 Total trihalomethanes less than 0.08 mg/L.
b.54 Total haloacetic acids less than 0.06 mg/L.
Part 3: Fluoride

All water being delivered to the project area for human consumption (at least one water dispenser per project) meets the following limits:

a.54 Fluoride less than 4.0 mg/L.
Respiratory
Integumentary
Reproductive
Digestive

Applicability Matrix

Core & Shell New & Existing Buildings New & Existing Interiors
Part 1: Disinfectants P P P
Part 2: Disinfectant Byproducts P P P
Part 3: Fluoride P P P
Commercial Kitchen Education Multifamily Residential Restaurant Retail
Part 1: Disinfectants P P P P P
Part 2: Disinfectant Byproducts P P P P P
Part 3: Fluoride P P P P P

Verification Methods Matrix

Letters of Assurance Annotated Documents On-Site Checks
PART 1 (Performance)
Disinfectants
Performance Test
PART 2 (Performance)
Disinfectant Byproducts
Performance Test
PART 3 (Performance)
Fluoride
Performance Test
42

National Water Quality Management Strategy. Australian Drinking Water Guidelines 6 Version 2.0. Canberra: National Health and Medical Research Council. 2011: 167.

34.1.a

The Australian Drinking Water Guidelines set an aesthetic guideline value of 0.6 mg/L of chlorine in drinking water.

54

Office of Water. 2012 Edition of the Drinking Water Standards and Health Advisories. Washington D.C.: U.S. Environmental Protection Agency; 2012: 2, 3, 5-11.

34.1.b

The EPA 2012 Edition of the Drinking Water Standards and Health Advisories notes that the 1998 Final Rule for Disinfectants and Disinfection By-products set a Maximum Residual Disinfection Level for Chloramine concentrations at 4 mg/L.

34.2.b

The EPA’s 2012 Edition of the Drinking Water Standards and Health Advisories notes that the 1998 Final Rule for Disinfection By-products set the total concentration for five Haloacetic acids at 0.06 mg/L.

34.2.a

The EPA’s 2012 Edition of the Drinking Water Standards and Health Advisories notes that the 1998 Final Rule for Disinfection By-products set the total concentration for trihalomethanes at 0.08 mg/L.

34.3.a

The EPA's Drinking Water Standards and Health Advisories set a Maximum Contaminant Level for Fluoride at 4 mg/L.