In this post, we are taking a closer look at the WELL Health Safety Rating air quality guidelines.

We are entering a serious phase of the COVID-19 response with cities coast-to-coast enacting emergency orders to limit spread. The good news about potential vaccines is a light at the end of the tunnel, and commercial real estate owners and operators are looking for smart ways to prepare for a safe re-opening and to communicate crucial information about COVID-readiness to building occupants and tenants.

We’ve extensively covered the COVID-readiness rating systems, and now we are looking more closely at the specific requirements that building operators need to consider as they choose the rating system that best aligns with their goals and values.

Let’s take a closer look at the WELL Health Safety Rating’s air quality features.

The WELL Health Safety Rating was developed to help building owners adapt to the COVID-19 pandemic. The WELL Health Safety Rating is based on the WELL Building Standard but has fewer features than a WELL certification. Additionally, achieving a WELL Health Safety Rating can contribute to a WELL certification.

Speed was top of mind for IWBI in developing the WELL Health Safety Rating, and the requirements of the rating are designed to be deployed quickly and without major investments. There are 21 design features to choose from, and Health Safety Rating requires achieving 15 of those features. There are five features in the WELL Air and Water Quality Management category, of which three apply to  air quality:

  • Assess ventilation
  • Assess and maintain air treatment systems
  • Monitor air and water quality

Assess Ventilation:

This WELL Health Safety Rating air quality feature requires projects to assess their ability to bring in fresh air from the outside through mechanical and/or natural means in order to dilute human- and material-generated air pollutants. The assessment addresses the highest supply rate of outdoor air the current system can provide; potential modifications to system controls to increase the supply of outdoor air; the extent to which the current system can operate without recirculating air; and how/if any of the potential HVAC system modifications would affect energy consumption, thermal comfort conditions, and maintenance processes.

This feature requires an assessment of what the system can handle but does not require minimum performance thresholds be met.

Assess and Maintain Air Treatment Systems:

This feature requires the project to inventory air filters and other treatment devices used throughout the building to ensure proper tracking and maintenance. This is important because particles exhaled by infected individuals that contain airborne diseases such as COVID-19 can remain suspended several hours or longer and can be recirculated through the ducts of the building.

To meet this requirement, projects need to provide an inventory of all filters and UVGI equipment currently used to treat the air in ducts and air handling units, fan coil units, and standalone cleaning devices. A qualified engineer will need to assess the highest efficiency of filter media or other particle filters that can be installed with the current mechanical system, and the capacity of the current mechanical system to utilize UVGI equipment. The project will need to provide either the conditions under which the project will install these treatment systems or a timeline for the installation of the treatment systems.

For devices identified in the System Inventory, the project must provide evidence that the filters and/or UV lamps have been replaced according to the manufacturer’s recommendation.

Monitor Air and Water Quality:

This feature requires projects to monitor air and water quality at least once a year. The World Health Organization (WHO) and other regulatory bodies such as the U.S. Environmental Protection Agency (EPA) identify a list of “criteria” air pollutants and have established permissible levels for such criteria pollutants based on epidemiological studies that show the relationships between concentrations of these pollutants, duration of exposure and health risks.

Each year, the following pollutants are monitored (or tested) in regularly occupied spaces:

  • 5 and/or PM10
  • Total VOCs and/or Formaldehyde
  • Ozone
  • Carbon Monoxide

Bottom Line:

The WELL Health Safety Rating offers building owners flexibility for older buildings where it may not be feasible to upgrade mechanical equipment or MERV efficiency at this time. It requires owners to understand their building’s capacity but doesn’t demand that they achieve any particular level of performance in order to achieve certification.

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  1. I’m a proponent of WELL building verification, but I am concerned the WELL health and safety rating is not up to par. With no thresholds, minimum filtration requirements, or minimum ventilation requirements, I’m concerned that the rating may create a false sense of health and safety, allowing workers to return to buildings that are no better than the building they abandoned at the onset of the pandemic, and no better than the building next door that didn’t pursue a rating. We must mandate air treatment solutions that are proven to work. This includes ionization, UV, and MERV-13 filtration on units that can accommodate this level of filtration. Outdoor air requirements must be tuned, not merely assessed.
    On the topic of relying on increased ventilation to reduce indoor pollutants, we must proactively plan for the inevitable air quality challenges of late summer forest fires and other outdoor pollutants.

    1. Interesting that you bring that up, Keith – we’ve had some lively discussions about the function and benefit of prerequisites around here as well. Our goal is to guide clients to pursue meaningful strategies that are back-checked by a certification. No system is perfect, so we work to fill gaps in the certification with our own expertise and best industry knowledge. There are some cases where the more rigorous requirements of other rating systems would be an impossibility because of the age of the building, or if the client can only control a tenant interior space, for example. In those cases, the WELL certification can still improve the safety and wellness of the space. The benefit of knowing the ins and outs of the leading COVID-readiness rating systems is that we can guide clients toward the option that is doable and effective within the context of their building.

  2. My husband and I are vigilant when it comes to yearly cleaning and maintenance of our Heating/CAC units in both our home and Class A RV.


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