Flush or Test? How to Pass LEED’s IAQ Testing the First Time

The right attention to detail can make all the difference during the LEED certification process. Both LEED 2009 and LEEDv4 contain prerequisite and credit requirements that offer different execution options to earn certification points--so how can you be sure you’re choosing the right option for your project?

This dilemma crops up especially in the indoor environmental quality (EQ) category for Building Design + Construction (BD+C) projects. Prerequisites and credits in this category require either a building flush or building air quality testing after construction--but prior to building occupancy--to ensure safe indoor air quality for its inhabitants. If your project is deciding which of these two methods to choose for certification, consider which option will be more beneficial for your time and budget.

Building Flush

To obtain credits for a building flush-out, the General Contractor is expected to install a new filtration solution and flush-out the project space after construction ends and before occupation begins. LEED requires a building flush to be executed by supplying a total air volume of 14,000 cubic feet of outdoor air per square foot of floor area, all while maintaining an internal temperature 60° and relative humidity of 60%. While many projects opt for building flush-outs to prepare their indoor air quality for occupation, the process can be incredibly time-consuming--a building flush usually takes at least 2 weeks, and in many cases can last up to a month.

Time is not the only challenge presented with a building flush. Flush-outs can also be difficult to accomplish if the project’s construction is completed at a time of year that isn’t conducive to maintaining the required temperature and humidity levels, and an added effort to meet these requirements can run up unexpected energy costs.

If the project’s construction schedule doesn’t allow time for a full building flush, many projects may attempt a phased flush-out. While phased flush-outs are an approved method for LEED certification, this method can also pose a challenge for certain projects. Phased flush-outs require 3500 cubic feet of outdoor air per square foot of floor area to be flushed out prior to occupation, then continual ventilation (at 0.30 CFM per square foot) after occupancy until the expected 14,000 cubic feet of air is reached. This option is usually much longer than the full flush-out, and the added challenge of building occupancy can make it much difficult to achieve the expected temperature and humidity levels.

Air Quality Testing

In many cases, opting for indoor air quality testing over a building flush can be the time and cost-effective solution for this credit. Indoor air quality monitoring can seem like a gamble--many projects may not choose this option because it may seem difficult or even impossible to pass. However, the IAQ test is a much faster process than the building flush and, if certain measures are taken to ensure that the project passes the first time, can actually be financially beneficial. But how can you ensure your project passes the test on the first try?

Pursuing your LEED certification? Download our one-sheet guide to learn how to  earn certification points with Awair Omni.

Follow these steps prior to the test date:

1. Keep VOC levels low

LEED indoor air quality testing is concerned with measuring your project’s levels of organic gases, known as volatile organic compounds (VOCs), present.

Keeping VOC levels low is crucial to ensure occupant safety and health. Regular exposure to VOCs can cause irritated eyes, throat, nose, and skin, and prolonged exposure has been linked to eczema flare-ups, hives, allergies, leukemia, and damage to the kidneys, liver, and central nervous system.

Building materials, carpets, furniture, fabrics, adhesives, solvents, and many more common materials can emit VOCs. In some cases, these materials can claim to be “VOC free” and still contribute to high total VOC readings during testing. To ensure your project truly has low VOC levels, make sure to use materials that are certified VOC free with strict certifications such as GREENGUARD, Floorscore, or Green Label Plus.

Paint is especially notorious for containing VOCs. If your project did not use VOC-free paint, be sure all painting is completed at least a week before the test date.

On a similar note, cleaning products can attribute high levels of VOCs to indoor air quality. Cleaning crews should not be scheduled sooner than 24 hours before testing.

2. Limit personnel present on testing day

Human activities can greatly affect indoor air quality readings, so try to limit the number of people present on the testing day to as few as possible. This can help avoid the risk of stirring up dust and particulate matter, and certain clothing, hair spray, perfumes, and colognes can increase VOC readings.

3. Maintain a proper airflow

A healthy air flow will be your best ally to help pass IAQ testing. Run HVAC systems at least 72 hours prior to the test date, and if outdoor air quality is at a healthy level, air out the building with outdoor air as well.

Take Control of Your Environment

Aside from these best practices, the one way to truly ensure your project’s indoor air quality is ready for testing is with the help of an indoor air quality monitor.  Air quality monitors, like Awair’s Omni business solution, track the factors that affect the quality of your indoor air and lets you know the moment your air is unsafe or unhealthy.

Aside from helping your project pass LEED’s IAQ testing the first time (WELLv2 is also an option), indoor air quality monitoring has been shown to give projects many financial benefits. Learn how to use Awair Omni to earn LEED points and streamline ARC reporting by downloading our one-sheet guide below.

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