Enhanced on-site testing process for WELL

On-site testing is one of the hallmarks of the WELL program. It is the process through which project teams demonstrate that their space is performing as designed and meets the rigorous requirements of the WELL Standard.

IWBI is proud to release updated program materials that aim to make on-site testing more streamlined, implementable and impactful for all. The technical requirements, processes and tools have all been refined. Access the revised program materials - including the PV Guidebook and the PIP tool.

Why are these changes important?

They allow WELL Performance Testing Agents (PTAgents) to:

Calculate the quantity of required samples per project easily and quickly.
Access an expanded network of eligible labs.
Follow clear and concise instructions in the guidebook.
Utilize an enhanced and powerful PIP tool to determine sample quantities, enter data and evaluate compliance automatically.

Overarching Changes

Guidebook Layout:

The layout of the guidebook has been reorganized for improved readability and usability. Previously, sample quantities, sample locations, test methods and other sections were organized and repeated for each parameter. In the new guidebook, these sections have been collapsed with parameter specific nuances listed. No more flipping back and forth between general requirements and parameter-specific requirements!

Guidebook Language:

The language in the guidebook has been revised to be more clear, concise and consistent. Now, PTAgents, consultants and project teams will have an easier time understanding the ins and outs of on-site testing, and explaining the process to key stakeholders.

Guidebook Introduction:

The introductory section within the guidebook now includes a more detailed list of elements that a PTAgent should familiarize themselves with in order to create a strong sampling plan.
This section has also been updated to include a more detailed list describing the documentation package that a PTAgent must submit for review.
Lastly, this section now explains the basics of the sample quantity calculations and sample location guidance and how to apply this guidance to projects of different sizes and configurations.

Sample Quantities:

The methodology used to determine the number of samples required per project for all project typologies including WELL Core and Multifamily Residential has been simplified. You will now input the project area into a straightforward formula to finalize sample quantities easily and quickly. Say goodbye to the complex calculation model that formerly considered extensive project details? PTAgents can now prepare more accurate and competitive quotes and proposals in far less time.
The PIP tool provides an easy-to-use calculator for PTAgents and any member of the project team to utilize when determining the required sample quantities for a project. Note: we recommend using the PIP tool rather than performing a manual calculation.
- WELL Core Projects: Each concept-section of the guidebook explains how to determine the required number of samples and what area (non-leased space and/or whole building) to utilize in the calculation.
- Multifamily Residential Projects: Projects with dwelling units no longer need to use separate, residential-specific formulas for determining sample quantity. Instead, for Preconditions, projects targeting Bronze or Silver certification utilize the area of common areas to determine the required number of samples and projects targeting Gold or Platinum utilize the total project area. See the language in the guidebook for specific instructions.

Sample Locations & Conditions:

Sample location guidance has been reformatted into a clear list of criteria, giving PTAgents more confidence when designing and documenting their sampling plans.
The sample location criteria are organized in order of priority from top to bottom. Depending on the project’s sample quantity, a PTAgent might not be able to fulfill the requirements for all of the sample locations, especially those lower on the list, before all available samples have been assigned a location. This is fine! Locations lower on the list do not need to be tested once total sample quantity has been allocated to locations further up on the list.
It is also possible that a PTAgent may have samples remaining after reaching the bottom of the list. In this case, PTAgents may take the remaining samples in any valid test location.
Each concept-section of the guidebook also covers requirements during testing such as what building systems should be on or off. For Air, Thermal Comfort and Sound, we clarified that user-operable windows must be closed during testing. (For buildings that are naturally ventilated, this excludes windows that are associated with the building’s ventilation system.)
If working on a WELL Core or multifamily residential project, each concept-section of the guidebook covers how distribute samples between leased and non-leased space (WELL Core projects) or common areas and tenant spaces (multifamily residential projects).

Device Requirements & Maintenance:

Based on extensive market research, calibration requirements for direct-read devices have been clarified. Instead of deferring to manufacturer specifications, the calibration period required for each device is now more clear. We have also extended the allowable calibration period for Light and Thermal Comfort direct-read devices, offering more leniency without sacrificing rigor. By articulating specific requirements, PTAgents now know exactly when and how their devices must be maintained to ensure rigor test after test.

Laboratory Accreditation and Test Methods:

In order to expand the global network of labs available to analyze samples for WELL, we made two key changes:
- Laboratories can now be accredited by a body authorized by the local government, even if that accreditation does not follow ISO 17025.
- We now describe the methods that must be used for analysis and list standard methodologies as examples. For example, to analyze formaldehyde, a laboratory may use any high performance liquid chromatography (HPLC) process for assessing indoor or ambient air quality, and examples include ISO 16000-3 and EPA TO-11. Thus, it is acceptable for the laboratory to analyze the sample according to (and be accredited for) an in-house process based on one of these standards, or any HPLC methodology.

Air

Quantity of Sample Locations for the Air Concept: A project that is 13,940 m² [150,000 ft²] would use the middle row of the table below and their formula would be as follows:
- (13,940 m² / 9,290 m²) + 4 = 1.5 + 4 = 5.5 → 6 samples (always round up)
- (150,000 ft² / 100,000 ft²) + 4 = 1.5 + 4 = 5.5 → 6 samples (always round up)
Test Methods: We added pathways to measure ozone, carbon monoxide and nitrogen dioxide using laboratory techniques that were previously allowed through published alternative strategies (including AAPs and EPs).
Laboratory-based Test Methods: As mentioned above, for each air parameter analyzed by a lab, we described the analysis method rather than the specific standards to be followed. For example, carbon monoxide must be evaluated using a gas chromatography/discharge ionization detector (GC-DID) method for ambient or indoor air quality such as OSHA ID-210.
Device Requirements and Maintenance:
- We clarified that direct-read devices used to measure air parameters on-site must be calibrated annually and in accordance with a reference standard traceable to a National Metrology Institute, such as NIST, NPL or PTB.
- Industry standards describing sample collection for laboratory analysis often describe the technical requirements for sampling pumps. However, since we now allow additional analysis methods, we clarified in the language of the guidebook itself that the sampling pumps must be calibrated by a separate flow meter prior to collecting each sample.

Water

Quantity of Sample Locations for the Water Concept:
Laboratory-based Test Methods: As mentioned above, for each water parameter analyzed by a lab we described the analysis method rather than the specific standards to be followed. For example, coliforms must be analyzed using a fermentation or membrane filter technique in accordance with 40 CFR 141.74(a)(1), ISO 9308 or a national standard for determining coliforms in drinking water.
WELL Core Guidelines: In combination with a new alternative adherence path published in the Q4 2024 addenda, we clarified a pathway for when testing can take place in non-leased space or from filtered water. This AAP formalizes the way WELL Core projects can document the previous requirement that water filters (if used) are provided to tenants. Per guidelines in the introduction to the PVGB, project teams will indicate to PTAgents any features in their scorecard that are met through an alternative strategy.

Light

Quantity of Sample Locations for the Light Concept:
- Visual Lighting
- Circadian Lighting
Sample locations & conditions: PTAgents are required to take lighting measurements according to a grid; sample placement guidance in reference to this grid were adjusted. Tests are now to be taken at the intersection points of the grid, rather than at an agent-selected location within each grid square. Further, grids are to be laid out by the PTAgent only in the rooms selected for testing, and not by project teams over the entire floor. This change was also reflected in the documentation requirements for WELL v2 Feature L02.
Reporting & Compliance: The requirement for Visual Lighting (WELL v2 Feature L02) was simplified. Specifically, the minimum measurement is no longer required to meet half the WELL threshold.
Device Requirements & Maintenance:
- Direct-read devices used to measure light parameters on-site must now be calibrated every 8 years, instead of at intervals specified by the manufacturer.
- Language has been added to remind PTAgets to dark calibrate when they power on the device.

Thermal Comfort

Quantity of Sample Locations for the Thermal Comfort Concept:
Sample Locations & Conditions: Tests for dry bulb temperature now are only required at one height instead of three heights, meaning that all thermal comfort parameters can be measured at the same height, 1.1-1.7 m [3.6-5.6 ft].
Device Requirements & Maintenance: Direct-read devices used to measure thermal comfort parameters on-site must now be calibrated every three years and in accordance with a reference standard traceable to a National Metrology Institute, such as NIST, NPL or PTB.

Sound

Quantity of Sample Locations for the Sound Concept:
Test Method: Test methodologies were unified for background noise levels (WELL v2 Feature S02) in different spaces in the project. Now, Category 3 spaces (e.g., dining areas) use the same methodology as spaces within Categories 1, 2 and 4. Agents will utilize a single 5-minute test, rather than 1 test per 500 ft² that are then averaged together to determine compliance.
Device Requirements & Maintenance:
- To expand the eligible pool of devices and help to make traveling to the project site easier for PTAgents, there is no longer a minimum size requirement for the speaker used for sound generation when testing for Sound isolation (WELL v2 Feature S03) and Reverberation time (WELL v2 Feature S04). The only requirements for the speaker are that it can generate 100 dB over a range of 100 Hz to 4 kHz.
- Measurement devices can now be calibrated every two years instead of each year, so long as a sound calibrator is used on-site during each day of testing.