This is a legacy version of the WELL Building Standard. Please check the latest version here.
  1. Air
  2. Microbe and mold control

Microbe and mold control

Features>Air>06. Microbe and mold control

06. Microbe and mold control

Intent: 

To reduce mold and bacteria growth within buildings, particularly from water damage or condensation on cooling coils.

Mold often grows on cooling coils in HVAC systems due to moisture condensation and can be introduced into the building’s indoor air. It can also occur on or within wall assemblies due to water damage or improper detailing in humid locations, for example kitchens and bathrooms. Mold spores can trigger asthma, headaches, allergies and other respiratory system disorders.

Part 1: Cooling Coil Mold Reduction

In buildings that rely on a mechanical system for cooling, one of the following requirements is met:

a. Ultraviolet lamps (using a wavelength of 254 nm so as not to generate ozone) are employed on the cooling coils and drain pans of the mechanical system supplies. Irradiance reaching the cooling coil and drain pan, including the plenum corners, is modeled.
b.9 Building policy states that all cooling coils are inspected on a quarterly basis for mold growth and cleaned if necessary. Dated photos demonstrating adherence are provided to the IWBI on an annual basis.
Part 2: Mold Inspections

The following are not present:

a.12 Signs of discoloration and mold on ceilings, walls or floors.
b.12 Signs of water damage or pooling.
Immune
Integumentary
Respiratory

Applicability Matrix

Core & Shell New & Existing Buildings New & Existing Interiors
Part 1: Cooling Coil Mold Reduction P P P
Part 2: Mold Inspections P P P
Commercial Kitchen Education Multifamily Residential Restaurant Retail
Part 1: Cooling Coil Mold Reduction P P P P P
Part 2: Mold Inspections P P P P P

Verification Methods Matrix

Letters of Assurance Annotated Documents On-Site Checks
PART 1 (Design)
Cooling Coil Mold Reduction 		MEP Drawing or Operations Schedule
PART 2 (Performance)
Mold Inspections 		Visual Inspection

9

National Air Duct Cleaners Association (NADCA). NADCA White Paper on Ultraviolet Lighting Applications in HVAC Systems. http://nadca.com/sites/default/files/userfiles/documents/2014/bod_final_.... Accessed October 8, 2014.
06.1.b

NADCA's White Paper on Ultraviolet Lighting Applications in HVAC Systems states that to avoid ozone production, use UVC lamps with a wavelength of 254 nm.
12

National Center for Healthy Housing and American Public Health Association. National Healthy Housing Standard. http://www.nchh.org/Portals/0/Contents/NHHS_Full_Doc.pdf. Published 2014. Accessed September 15, 2014.
06.2.b

The National Healthy Housing Standard states that the foundation, roof, roofing components, exterior walls, doors, skylights and windows shall be free of persistent dampness or moisture.
06.2.a

The National Healthy Housing Standard states that building materials affected by mold or mildew should be cleaned, dried, and repaired. It also states that interior and exterior surfaces shall have no signs of visible mold growth.
Features>Air>06. Microbe and mold control