Hi Dick we have used the safety siren for past number of years as a unofficial post mitigation device. We post test with short term e-perms and a long term alpha track but because in Canada we have most of our fans indoors we wanted something with an alarm on them to react to a potential leak. We bench test these devices when they come into our office 12 at a time, most are fairly accurate once they get to 4 days. Our last few batches however have had between 3/12 and 1/12 have to go back to manufacturer as inaccurate or non functioning. We have decided to go another way and recommend radon eye or corentium monitor be purchased by homeowner rather than have safety siren on the truck to sell at little mark-up.

Hi Dick,

We have been selling the units since the late 1990's. We don't use them in our work but provide them for clients that want them. We have had little issue with the units over the years, in our experience they have been reliable.

I do not use them in my business, but have done several side by side tests for clients that have them, with my CRM's. Most of the time they are pretty close to my calibrated CRM's however I have found a few that have been wrong, giving higher averages than I showed. I believe the SS's that were off were in the warranty period and were either replaced or recalibrated by manufacturer.

I have had similar problems with Safety Sirens seeming to read high compared to my crm, or having a large spread in readings between units. In one instance, post mitigation, and with crm readings around 20, I eventually had three Safety Sirens (mounted on a wall) 8" apart with readings ranging from 40's to close to 200. Maybe radon is that finicky sometimes, and maybe mounting them on a wall isn't the best, but they've caused me some grief, especially in having to deal with remote locations where trouble-shooting is a little more difficult. I've also had problems, where the electrical power is perhaps dodgy, with monitors giving super-high readings, showing errors, or showing displays that aren't in the manual. I replaced with the battery powered option in those cases as well.

My home Safety Siren was reliable until it past it's warranty period and sensor failed. My neighbour had one that post mitigation was readying around 150 to 180 Bq/m3 (4 to 5 pCi/L). I used two RSSI alphas co-located beside the instrument and the RSSi's reported radon around 15 to 20 Bq/m3.

I am glad to see a civil discussion of the Safety Siren Pro 3. I have been selling this unit for 5 years. When I do get returns from customers who mark it as "defective" it either means they are truly defective or an unscrupulous customer just wants to take advantage of the liberal 30 day return policy to use the unit and then return it within 30 days. When I test these "defective" units against others returned, and with new units, I have found they are quite consistent in their readings. That does not mean they are "accurate" compared to some perfect standard, but consistent with each other. When I do get an outlier, or one with an error message, I send it back to the factory for replacement and they are very good about that. That probably happens to only about 5 out of 100 returned "defective" units tested.

Based on many tests I believe the unit is reliable enough to serve home owners as a first alert to determine if there is a radon problem that needs to be fixed. Protocol says that if you get a high reading test again with another device or call in a professional to confirm it.

Good point Jeff. Things need to stay civil. We all remember why the last list server was shut down and I don't want that happening to this list serve.

Safety Siren did a lot of work in this field which got more people testing for radon and which brought value to the industry and I think they deserve credit for that. I don't believe the manufacture ever pushed that the Safety Siren was a CRM or that it should be used as such.

If we keep in mind the intent and purpose of the Safety Siren we realize it does its job as it was designed to. All devices have their limits and intended use and as such are not good or bad per say. This is the same for any air quality monitor out their. All manufactured devices are subject to wear and tear. Remember smoke and CO detectors also eventually fail but I still sleep better knowing I have them. I have always specified a Safety Siren or equivalent in all my mitigation designs so that occupants are left with a warning device should something go wrong with the mitigation system. There are newer electronic home radon monitors on the market that also function within the intended design and purpose but they will have their own set of limitations, again not good or bad per say. In my opinion and experience in indoor air quality most of the issues with direct read instruments is not the fault of the device but the fault of the user not using the device properly.

One thing to be aware of: in my experience, most of the people I know who have Safety Sirens do not follow the manufacturer's recommendations for recalibration. If my memory is correct, that recommendation is to send the unit back for recalibration once per year, at a cost equal to about 60% of a new unit.