Warning: Do not store vintage watches with radium lume in an air tight box!

So I found out that my friend had a portable radon monitor and he let me borrow it for a few days.

I have a watch from 1955 with a bit of radium lume. It's a dress watch so the lume area is quite small. I previously used a geiger counter to measure the radiation and it clocked in at 1.3 microsieverts per hour from the dial side, and 0.5 from the caseback. This is pretty minimal so I don't worry about wearing the watch. However, I've been storing it in an air tight container to prevent any potential radon gas from filling up my room.

Well, I put the radon monitor inside the box to see if my watch did actually give off any radon gas. I waited a day for the result. When I came back, the device showed a measurement of 1800 bq/m3!!!!! My house has a background radon level of 30 bq/m3 so this is more than 50 times the amount.

And guess what.. I left the monitor inside the box for a few more days and it continued climbing. I eventually pulled the plug at 3000 bq/m3 and put the watch in a well-ventilated shoe closet near the door.

Now that I think about it, this should have been pretty obvious. The watch gives off radon gas, and even if it's gives off a minuscule amount, it will continue building up if it's stored in an air-tight container. At this point, I would be scared of putting a watch with radium lume in a watchbox... Even if it's not completely airtight, the radon gas will accumulate. And if you open the box, you are getting a hit of highly concentrated radon gas. You will probably need to be exposed to it thousands of times for it to pose any risk, but still, your health is not something to take chances with.

Thankfully, I was always semi-aware of this potential issue and only unlocked the box outside my room. But I'll be storing the watch in an open area from now on that's well-ventilated.

The good news is that Radon has a half life of 3 days so it's not like the measurement will climb to an infinite level if left inside the box forever. However, radon decays into radioactive lead and I don't want my storage container to be coated in radioactive lead particles..

Just thought I would share.

Haven't found much discussion regarding the potential issue of storing watches in an air tight container. In fact, I've stumbled upon multiple recommendations from here that advised you to store watches in an air tight container if you want to avoid radon gas from filling up the room. This is in fact why I started doing it in the first place.

Not sure why you are linking my previous threads as if they undermine what I'm saying. How are they relevant to this discussion?

I'm also talking about something different and referring to a specific situation where you store radium watches in containers. I'm sure a lot of people store their watches (radium or not) in a watch box so this is in fact relevant for most people.

I'm not trying to fear monger here.. I actually measured the levels with a radon monitor and I'm just simply sharing what I found. Sorry if this makes you feel uncomfortable.

I never got suspended. Why are you making stuff up?

I admit I was being somewhat irrational in the previous threads (which was almost a month ago) but I'm talking about a different type of risk Sorry if you lack the critical thinking skills to differentiate the two. Oh btw, why do we have millions of comments here talking about this same thing called a watch?

And honestly, what's bad about trying to spread awareness of things like this? If this saves some uninformed individual in the future from inhaling a hit of radon gas every day, then isn't it a good thing? Why are you trying so hard to be dismissive? If you don't want to discuss it, you don't have to comment.

Are you saying that since the box I measured it in is less than 1 m3 in volume, the device is overstating the numbers?

When I put the radon meter in an empty air-tight box, the level is not any different than the normal levels of radon in my house even if I leave it inside for a day. So the fact that I got a measurement 50x higher when I had the watch in the box does indicate that there's definitely a build up of significant radon gas in the box. Yes, the box is small so in the end, the total radon gas in the box is not a major amount. But it's still something to keep in mind.

I have no doubt that the measurement would be lower if the box was bigger. But over time, as long as it's air-tight, the gas will still accumulate inside it.

So with a bigger box, the max level of radon will be lower. My air-tight box was small but I would guess that it's only about half as small as a normal watch box.

Also, keep in mind that radon gas decays into radioactive lead particles, which will gradually build up in your watch box over time. These have a half life of 22 years so it's more or less permanent. I couldn't find much info online on the significance of this as it's usually not a concern in real life, but it's something to keep in mind.

I found your comment about the sealed box interesting and useful, but I don't own any radium watches so don't have the same concerns.
I mainly want to comment on the above statement however, as I've seen another member say something about "if you're too illiterate to understand" on another thread recently. These passive aggressive taunts aren't useful and are a bit childish, they always turn me off. Please refrain from such rudeness if you want to be taken seriously here, and in life in general.

It was for that specific thread only. Far from what a typical "suspension" on a forum looks like.

yes, don't address the rest of my comments because your cognitive dissonance is too strong to overcome so you would rather ignore the risks than be informed of it.