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What is a Radon Survey?

Includes short-term and long-term sampling

A radon survey is a test conducted by knowledgeable and qualified radon specialists to identify the presence and levels of radon in a commercial real estate structure. These tests include short-term and long-term radon sampling, sampling for Freddie Mac, Mannie Mae and HUD guidelines, and radon mitigation testing.

What is Radon?

Radon is a colorless, odorless radioactive gas that is produced when uranium in the soil decays. Ordinarily, radon then moves up from the soil and into the atmosphere, where it dilutes and doesn’t pose any health risks. When radon enters a closed structure, such as a dwelling, office, or apartment building, it accumulates and presents a health hazard for the occupants that breathe it in. Exposure to radon typically happens through ingestion and inhalation, with inhalation being the largest threat of developing lung cancer. 

Although radon exposure is a bigger concern for residential homes, where people spend more prolonged time over a daily basis, radon can enter commercial buildings the same way it does residential ones. Certain categories of commercial buildings, such as offices, schools, day cares, long-term hospitals and facilities, and multi-family residential properties, are susceptible to dangerous radon exposure and may even be subject to certain regulations.

Radon is measured in picocuries per liter of air (pCi/L), which is a measurement of radioactivity. There is no “safe” level of radon exposure is known to exist. However, the EPA’s recommended action level is 4.0 pCi/L.

How Does Radon Enter a Structure?

Radon commonly poses the greatest threat to residential occupants living at or below the ground surface. However, radon can build up to dangerous levels inside any structure, whether it be new, old, with a basement or without a basement. Typically, radon can enter a structure through:

●Cracks in floors and walls
●Gaps around service pipes and gaps in suspended floors
●Cavities inside walls
●Construction joints
●Water supply 
●Varying levels of uranium in some granite finishes

When Should a Radon Survey Be Conducted?

High levels of radon are prevalent in every state across America. Radon that originates in the soil is the main source of long-term exposure by seeping up from the ground through cracks and other holes and gaps in a building’s foundation. Indeed, approximately 75% of all radon tests occur because of a real estate transaction. The EPA identifies radon risk through its Map of Radon Zones. This map is a tool that can be used by national and state organizations, as well as environmental professionals, to approximate areas of high average indoor radiation (zone 1), medium levels (zone 2), and the lowest levels of indoor radon concentrations (zone 3). High levels of radiation have been found in all three map zones, however. The only secure way to accurately assess radon risk is through site-specific testing by a licensed environmental professional.

Radon Testing and Remediation

There are several types of radon surveys that can be performed, depending on the type of commercial real estate structure, the risk of radon presence, and the necessity for accurate results.

Short-Term Radon Testing:
Short-term radon tests are used to obtain fast results, usually for imminent commercial real estate transactions.  Short-term tests should be conducted for at least 48 hours, but can remain in the structure from 2 to 90 days, depending on the device. Additional testing is sometimes recommended to better assess the average radon level and to account for fluctuations.

The EPA recognizes several measurement standards that have been compiled by the Approved American National Standard and American Association of Radon Scientist and Technologists (ANSI/AARST).  These measurement standards include protocols for single-family homes, multi-family homes, schools and large buildings.

Long-Term Radon Testing:
A long-term radon test is the better indicator of the average radon level in your structure. Per the EPA, long-term tests can also be used to confirm initial, short-term results between 4.0 pCi/L and 8.0 pCi/L. Long-term tests must remain in the structure for more than 90 days, and in some scenarios, up to 12 months. The advantage of performing a long-term test is a reading which is more likely to depict the structure’s year-round average radon level, considering fluctuations during time of day, temperature change and even season. Radon levels increase in colder months.

Radon Testing for Lending Institutions:
Freddie Mac has specific radon sampling requirements for their multi-family deals. Additionally, the United States Department of Housing and Urban Development (HUD) Multifamily Accelerated Processing (MAP) requires radon testing guidelines (following protocols set by Multifamily Building Measurement [MAMF 2017] or states, whichever is more stringent) for multi-family units. Any HUD-backed financing or refinancing for a multi-family building must have radon testing performed by a radon professional and proof of radon mitigation for any unit that exhibits high levels of radon gas.

Radon Mitigation

The EPA recommends radon mitigation when long-term test results indicate a radon concentration of 4.0 pCi/L or higher. Commercial real estate transactions may be delayed until the seller has successfully abated radon to a level less than 4.0 pCi/L.

Common radon mitigation methods, such as Sub-Slab Depressurization (SSD) are simple to implement and relatively inexpensive. When installed correctly, by a certified radon remediation professional, a mitigation system can typically reduce radon concentrations from 80% to 90%.

Radon testing is accurate, inexpensive and easy. Radon reduction systems are available that can reduce 99% of radon levels in a structure. Radon specialists, certified either through the National Environmental Health Association National Radon Proficiency Program or one of the twenty state-specific radon mitigation and measurement professional standards, can identify radon risk and provide a feasible, effective solution to protect property investment and the health of its occupants.