OCRMI radon measurement

The OntarioACHI Certified Radon Measurement Inspector program is designed to provide the necessary skills to Home Inspectors enabling them, primarily, to provide short-term radon measurement inspections as part of a real-estate transaction.

The reasoning behind this program is to increase the amount of testing across Ontario of radon levels in homes.

Traditional radon tests are aimed at identifying the average annual risk to inhabitants of buildings from levels of radon in the building.    We at the Ontario Association of Certified Home Inspectors have taken a different approach. 

  • We know there are countless scientific documents, statistics and reports that explain increased exposure to radon, whether it be through time exposure or level exposure or a combination of both increases the risk of lung cancer.
  • We already know that over 850 Ontarians die every year from lung cancer caused by radon.
  • We know that the average background radon levels are between 20Bq/m3 to 45Bq/m3 in the majority of places in Ontario.
  • We know that reducing indoor radon levels reduces the long-term risk of contracting lung Cancer caused by radon inhalation.

Our approach has been to train our inspectors to look for possible defects, in our homes and properties, that allows radon to enter and level to build-up.

Recognising the risks

We respect that Health-Canada has a radon action level of 200Bq/m3, however, we are also aware that this appears to be an arbitrary number, distinctly different from the U.S. Environmental Protection Agency’s (EPA) action level of 148Bq/m3 or the World Health Organisation’s (WHO) reference level of 100Bq/m3.

Our basis for short-term testing is based upon Canadian, the U.S. and global research that all confirm, being exposed to lower levels of radon for shorter periods of time drastically reduce the likelihood of contracting lung cancer caused by radon inhalation.

For example The number of deaths, in Ontario alone, due to the inhalation of radon, could be reduced by 233, each year, if the indoor levels of radon were reduced to the WHO recommended remediation level.

The graph was created from data in
Lung cancer risk from radon in Ontario, Canada: how many lung cancers can we prevent?
E. Peterson, A. Aker, J. Kim, Y. Li R. Copes & K. Brand

Similarly: The number of deaths could be reduced by 389 if the indoor levels of radon were reduced to 50Bq/m3. That’s EVERY YEAR in Ontario.

The graph was created from data in
Lung cancer risk from radon in Ontario, Canada: how many lung cancers can we prevent?
E. Peterson, A. Aker, J. Kim, Y. Li R. Copes & K. Brand

The choices for testing

There is a number of choices for people who want to have a home or commercial property tested for radon levels. There are short-term, long-term, professional and DIY tests. However, the one limiting factor for the poor level of testing appears to be apathy.

In a recent survey it was found that 96% of Canadians had NOT had their homes measured to establish ANY level of radon.

Indeed, in the statistical analysis of homes across Canada, Health-Canada published the “statistical fact” that 7% of homes were above their radon action level. These statistics were based upon as few as 7 homes tested across a region with over 500,000 homes. Hardly representative.

At OntarioACHI we recognised if we were ever to get representative statistical analysis for levels of radon, we would have to think of something different.

All of our OCRMI inspectors have been trained to perform that normal 3-month and U.S based 48 hour type measurement, but we wanted to go further.

For radon to enter a home and build-up there has to be a defect in the soil to home envelope layer, or there has to be components in the home that are uranium containing and produce their own radon.

The key word here is “Defect”. This is what home Inspectors look for. We are not bothered about the long-term averages or the long-term health effects. These are well known.

We want to identify if your home has radon in it, what the levels might be, and preferably, let you know BEFORE you buy. This is why we developed the OCRMI short-term protocol to be used as part of the Real-Estate transaction.

Traffic light results

The OCRMI protocol, short-term measurement gives a clear, concise and unambiguous report on what was found at the home during a short-term (48 hour) test of the home.
This measurement is recommended to be performed during the sale process of the home, but there is nothing to stop consumers from requesting this measurement at any other time.
But wait, there’s more…..

OCRMI Ultra-short measurement

As part of their training, and OCRMI professional is taught that, by using a Constant Radon Monitoring system, they can provide an indication of possible radon infiltration into a home DURING a home Inspection.

That’s right. I the two and a half-hours it takes to perform a Full Home Inspection in compliance with the Canadian Standards Authority CAN/CSA A770-16 home Inspection Standard, a properly qualified OCRMI Professional can ALSO provide you with an indication of a possible defect to the home that allows radon entry and possible build-up.

How long does this add to the inspection?

About 5 minutes. The OCRMI Professional needs to set-up the monitoring device at the start of the inspection, and then check the settings at the end of the inspection. As long as the Inspection has taken longer than 2 hours, the monitor will allow the inspector to capture the radon level reading.

How much more will it cost?

A Constant Radon Monitor (CRM) is not cheap. Most units cost in excess of $1,500. Plus they need regular re-calibration and Quality Assurance testing to ensure accuracy. Most OCRMI inspectors will charge between $50-$100 (plus tax) for an Ultra-Short as part of the Home Inspection. You get OCRMI Ultra-Short report immediately at the end of the measurement.

What can I expect?

The best way to answer that question is to show you.
Remember, the OCRMI Ultra-Short measurement can ONLY be performed as part of a Full Home Inspection and ONLY using a CRM.
The type and approximate age of the home will be known. So will the construction methods. The location of the device will be reported on and, in contrast to the Green-Amber-Red report of the Short-Term report, the actual radon level readings will be presented.

This image has an empty alt attribute; its file name is Screenshot_20180914-124241_Pro-576x1024.jpg
House 1

The “House 2” reading was reading from a multi-split, 2-storey home, again, in Burlington.
It was about the same age and construction as the one above. Part of the basement was unfinished, at it had a sump pump.
The reading here was 151 Bq/m3 after 2 and 1.2 hours. Again this was higher than the background level of 35 Bq/m3 but less than the ‘magic’ 200 Bq/m3 that Health-Canada recommend remediation for.
Given that we know reducing radon to below 50 Bq/m3 greatly reduces the risk of contracting lung cancer from radon inhalation this level is still meaningful. You might want to follow the ultra-short up with an OCRMI short-term or even a long-term measurement, but the fact that radon is getting into the home gives you the option to choose to have the home pro-actively repaired.

The “House 3” reading was from another multi-split, 2-storey home in Hamilton. This home was no more than 3 km from house 1 and 2. Again, poured concrete foundation and an unfinished basement. The measurement was performed in the basement.
Here, there results were about on par with the background level. This doesn’t mean that the home didn’t, or wouldn’t in the future have high levels of radon, but at the time of the 2 and 1/2 hour inspection there were not great increases in interior radon.

The “House 1” reading was from a 15 year-old, 2-storey, timber framed, brick and vinyl clad home in Burlington, Ontario. The home had a poured concrete foundation and a finished basement.
The was no sump-pump in the home and no visible penetrations through the basement slab.
After 2 and 1/2 hours, including the home NOT being closed for 12 hours prior to allow radon levels to build-up, we got a reading of 251 Bq/m3. Sure it wasn’t a long-term average, but as the external background radon level was around 35 Bq/m3 this was a prime indicator that radon was entering the home and could over time build-up.

House 2
House 3

In the case of ‘House 4’, using a different CRM, a measurement was performed over 48 hours, with closed house conditions. A timber framed, poured concrete home, with an unfinished basement and the measurement performed on the ground floor we can see the radon levels were around 220 Bq/m3. Background levels were at or around 45 Bq/m3 so again this home had a clear indication of a defect allowing radon entry and build-up. This home is in Niagara Falls.

We can see from the time graph that the levels peaked over 293
Bq/m3. While the Health-Canada guidelines would recommend long-term testing, it is clear that something is going on here, and the OCRMI protocol would recommend talking to a professional mitigator and getting the home fixed ASAP.

The sublime to the ridiculous.

For those who think they don’t have a problem. Every once in a while we come across a home that knocks that theory out of the park.

Here’s the reading from a 2-storey home, in Niagara Falls. Poured concrete foundation, no sump. The home is old (built in 1907) and is a drafty as a breezy day in the Grand Canyon. No air sealing anywhere so should have little stack-effect and really good ventilation.

Performed a 67-hour measurement with the CRM in the basement expecting slightly higher than background levels.

On the left is the average radon level over the 67 hours. You can see that the level goes up and down. This does not correlate with temperature pressure or humidity changes or the opening and closing of doors.
At its highest level over the period measured, the level peaked at 381
Bq/m3. At no point in time did the level drop below 100 Bq/m3, the World Health Organisations recommended lower level.

It is precisely this unpredictability as to when radon will enter the home and how much the levels will rise to is why we created the OntarioACHI Certified Radon Measurement Inspector program and why we feel you should choose an OCRMI professional to measure the levels of radon in your home either at the time you are purchasing it, or any other time you would like to really know the risks your home may be exposing you to.