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05-17-2018, 07:55 AM - 1 Like   #1
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Lens Radiation Revisited. This time with the State of Arizona involved !

I wanted to know just how much Radiation my Taks and other lenses that were radioactive were emitting.
I contacted the State of Arizona Department of Health , Bureau of Radiation Control. A gentleman came out to my house and looked at a Ice chest where I store My lenses.
His name is Stuart Steen.
He brought along two meters and immediately got a Gamma reading of 170 micro rems before the Ice chest was even opened.
We opened several lens cases and took measurements directly off the lenses at random.
He was very surprised that the readings he got were as high as they were , and suggested that I didn't sleep in close proximity !
So what I have learned is that through the decay chain of thorium glass , not only is it Alpha and Beta , but Gamma is also emitted.
Now everyone is different , but for my health concerns this was too much , and Mr Steen suggesting that they were best kept in a safe place away from me was eye opening.
I have gone from being one of the Radiation scoffers , to want to be playing it on the safe side.
I know this is going to open another can of worms on this subject , but please remember we are all different. What one person isn't affected by , can be cumulative to someone has DNA problems already.
I don't like my Tak collections anymore and will be selling all of them. Its not worth my personal health anymore to have an added risk.
Mr Steen was very nice , and rather informative.
I don't know the conversion of micro rems to milli rems or any of that stuff and it is confusing.
I hope someone that is really knowledgeable can chime in , but PLEASE.....no arguing and fighting as I want this to stay civil.


Last edited by Ronald Oakes; 05-17-2018 at 08:02 AM.
05-17-2018, 08:27 AM - 1 Like   #2
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Could you be more specific about which Taks you own, which were measured, and what those measurements are?
05-17-2018, 08:34 AM - 1 Like   #3
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A microrem is an incredibly small amount -- 1/1000th of a millirem. Consider that you are exposed to 300 or so millirems yearly just living (slightly more at higher altitudes).

Do you know what the close-up readings were like?
05-17-2018, 08:34 AM - 6 Likes   #4
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QuoteOriginally posted by Ronald Oakes Quote
He was very surprised that the readings he got were as high as they were , and suggested that I didn't sleep in close proximity !
QuoteOriginally posted by Ronald Oakes Quote
I don't like my Tak collections anymore and will be selling all of them.

It would be interesting to know if the eventual buyer of your lenses is a "Mr S Steen"...

05-17-2018, 08:45 AM - 1 Like   #5
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QuoteOriginally posted by tvdtvdtvd Quote
Could you be more specific about which Taks you own, which were measured, and what those measurements are?
I own Taks from the 28mm all the way up to the 300 series of taks.
The one that was the obvious offenders was the 50mm 1.4.
We didn't check each one individually , and a couple of the 300mm lenses didn't seem to register at all.
To do isolated precise measurements requires much more than sticking a meter up to a lens , and has to e done in a controlled environment.
However.....In spite of this , significant levels of Gamma was read directly through the ice chest.
I don't understand all the numbers , but readings as high as 300 micro rems of gamma were detected overall coming from my entire collection.
Im pretty shook about it all.
When someone advises me to store them in a lead lined case , that's enough for me.
We didn't have time to check each one individually , and that wasn't my concern in the first place.

---------- Post added 05-17-18 at 08:47 ----------

QuoteOriginally posted by BigMackCam Quote
It would be interesting to know if the eventual buyer of your lenses is a "Mr S Steen"...
NO.....he has no interest in them at all. He is a state employee.
05-17-2018, 08:54 AM - 2 Likes   #6
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Gamma readings before opening the ice chest is to be expected...pretty much only thick lead blocks gamma rays.
05-17-2018, 08:57 AM   #7
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QuoteOriginally posted by Ronald Oakes Quote
...I don't like my Tak collections anymore and will be selling all of them. Its not worth my personal health anymore to have an added risk...

1 millirem = 1000 microrems. (PF community, holler if I wrote that wrong)



I'm curious about shipping those lenses; they could set off security scanners at USPS, FedEx, etc. I just did a quick check of the USPS regulations and found this: "The radiation level at any point on the external surface of the mailpiece must not exceed 0.5 millirem per hour".


That's equal 500 microrem when measured on the outside of the shipping box. You said 170 microrem total on the exterior of your storage chest, under the limit, but readings increase as you get closer.


What was the highest reading you got directly off any of your lenses? If any lenses exceeded 500 at close range, pack them in an oversize box. If anything came way over 500 you might need additional shipping measures.
05-17-2018, 08:57 AM - 1 Like   #8
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QuoteOriginally posted by vonBaloney Quote
A microrem is an incredibly small amount -- 1/1000th of a millirem. Consider that you are exposed to 300 or so millirems yearly just living (slightly more at higher altitudes).

Do you know what the close-up readings were like?
The readings from one lens was as high as 170 micro rems , and it seemed to go out at least 3 feet from a lens and that was the Tak 50mm 1.4
I believe and he was only checking Gamma. Supposedly these don't emit gamma , but mine sure do as he described how the decay chain is initiated after several years and Gamma IS emitted.

Because of my genetics , current cancer risks , etc.....I wont be playing with them anymore. That's just me !
It may have nothing to do with anything , but I don't want the cumulative risk , and DNA damage anymore than I already have.

I know everytime I would get in lenses and camera orders from Goodwill. They always smelled like mildew or mold and I got Blazing headaches !

---------- Post added 05-17-18 at 08:59 ----------

QuoteOriginally posted by timw4mail Quote
Gamma readings before opening the ice chest is to be expected...pretty much only thick lead blocks gamma rays.
That's what he said. Im having trouble wrapping my head around the readings he used Micro Rems ?

---------- Post added 05-17-18 at 09:00 ----------

QuoteOriginally posted by DeadJohn Quote
1 millirem = 1000 microrems. (PF community, holler if I wrote that wrong)



I'm curious about shipping those lenses; they could set off security scanners at USPS, FedEx, etc. I just did a quick check of the USPS regulations and found this: "The radiation level at any point on the external surface of the mailpiece must not exceed 0.5 millirem per hour".


That's equal 500 microrem when measured on the outside of the shipping box. You said 170 microrem total on the exterior of your storage chest, under the limit, but readings increase as you get closer.


What was the highest reading you got directly off any of your lenses? If any lenses exceeded 500 at close range, pack them in an oversize box. If anything came way over 500 you might need additional shipping measures.
His readings were in Micro Rem not Milli Rem

05-17-2018, 09:04 AM - 1 Like   #9
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QuoteOriginally posted by Ronald Oakes Quote
I own Taks from the 28mm all the way up to the 300 series of taks.
The one that was the obvious offenders was the 50mm 1.4.
We didn't check each one individually , and a couple of the 300mm lenses didn't seem to register at all.
I asked because this event has given you the conclusion that all Taks are 'bad'.
QuoteQuote:
I don't like my Tak collections anymore
The 50/1.4 is well known to be radioactive. The 300mm's are not. However, it is not reasonable to conclude the collection is radioactive.
If you had a banana in the ice chest it too would be part of the collection that was emitting radiation. Bananas too are ever so slightly
radioactive, maybe more so than the 300mm's.

I do encourage you to read up on radioactive lenses and radioactivity in general.

---------- Post added 05-17-2018 at 11:09 AM ----------

QuoteOriginally posted by Ronald Oakes Quote
lenses and camera orders from Goodwill. They always smelled like mildew or mold and I got Blazing headaches !
I am pretty certain radioactivity doesn't cause mold. I'm also pretty certain mold doesn't cause radioactivity, at least not in
camera lenses.
05-17-2018, 09:22 AM - 1 Like   #10
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QuoteOriginally posted by tvdtvdtvd Quote
I asked because this event has given you the conclusion that all Taks are 'bad'.

The 50/1.4 is well known to be radioactive. The 300mm's are not. However, it is not reasonable to conclude the collection is radioactive.
If you had a banana in the ice chest it too would be part of the collection that was emitting radiation. Bananas too are ever so slightly
radioactive, maybe more so than the 300mm's.

I do encourage you to read up on radioactive lenses and radioactivity in general.
No.....I love my Taks !
Hmm....I cant eat Bananas.....lol.
05-17-2018, 09:22 AM - 1 Like   #11
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QuoteOriginally posted by Ronald Oakes Quote
NO.....he has no interest in them at all. He is a state employee.
That's what he told you, Ronald... but back at the office his nickname is "Lens Guy"

Seriously, though, it's pretty interesting stuff.

All my vintage lenses are in a cupboard in a separate bedroom, and I only ever use them for a short period at a time - and even then, not every day. It's possible that two or three of them are radioactive, but I figure the risks are extremely small given my use case.
05-17-2018, 09:24 AM - 1 Like   #12
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I just called him back. His readings were in Micro. He stated that we were getting readings 15x higher than background Gamma from several lenses.

---------- Post added 05-17-18 at 09:25 ----------

QuoteOriginally posted by BigMackCam Quote
That's what he told you, Ronald... but back at the office his nickname is "Lens Guy"

Seriously, though, it's pretty interesting stuff.

All my vintage lenses are in a cupboard in a separate bedroom, and I only ever use them for a short period at a time - and even then, not every day. It's possible that two or three of them are radioactive, but I figure the risks are extremely small given my use case.
DONT mess with my head like that please.....lol
05-17-2018, 09:54 AM - 2 Likes   #13
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Did Mr Steen say micro rems per hour, per day, per year, or what? Micro rems is a measure of accumulated dose over time. not a measure of the rate of radition. Without knowing the time frame of the rate measurement, it's impossible to gauge the relative risk. (Note: other articles about this issue and Mr Steen's 15X comment seem to be consistent with it being microrems per hour)

It's also important to note the distance to the source during measurement and during your exposure to the lenses. Readings (and exposure) from half a foot away will be four times higher than readings from one foot away. And if the 170 micro rems readings on the closed ice chest where done from 1 foot away from the lenses inside, then your exposure while being 10 feet away will be only 1.7 micro rems and staying 20 feet away would reduce exposure to only 0.4 micro rems.
05-17-2018, 10:01 AM   #14
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QuoteOriginally posted by photoptimist Quote
Did Mr Steen say micro rems per hour, per day, per year, or what? Micro rems is a measure of accumulated dose over time. not a measure of the rate of radition. Without knowing the time frame of the rate measurement, it's impossible to gauge the relative risk. (Note: other articles about this issue seem to be consistent with it being microrems per hour)

It's also important to note the distance to the source during measurement and during your exposure to the lenses. Readings (and exposure) from half a foot away will be four times higher than readings from one foot away. And if the 170 micro rems readings on the closed ice chest where done from 1 foot away from the lenses inside, then your exposure while being 10 feet away will be only 1.7 micro rems and staying 20 feet away would reduce exposure to only 0.4 micro rems.
It was Micro Rems per hour. It was when we opened several lenses and took them out of the cases that the highest readings were obtained. It was also distance related. after about 4 feet the Tak 50mm 1.4 was still higher than background , but not significantly.
Up close on one end it was quite obvious.

Im still trying to figure out just how equivalent a Micro Rem equals.
05-17-2018, 10:04 AM - 1 Like   #15
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QuoteOriginally posted by Ronald Oakes Quote
I don't like my Tak collections anymore
QuoteOriginally posted by Ronald Oakes Quote
No.....I love my Taks !
It appears the Mirror, Mirror Ronald has crossed into our universe.
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