
Pentax Camera Radiates 2.7µSv - nipponese
https://www.youtube.com/watch?v=oSeZqIWX2Ko
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hatsunearu
Apparently lenses can be radioactive:
[https://camerapedia.fandom.com/wiki/Radioactive_lenses](https://camerapedia.fandom.com/wiki/Radioactive_lenses)

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dngray
Yes, more specifically
[https://en.wikipedia.org/wiki/Thoriated_glass](https://en.wikipedia.org/wiki/Thoriated_glass)

also:

[https://www.youtube.com/watch?v=sHjCKiXDIDc](https://www.youtube.com/watch?v=sHjCKiXDIDc)

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ngcc_hk
I thought common knowledge. Some old lens used radioactive elements. But I was
under the impression the glass protect quite a bit of it.

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anticodon
I've read that good isotopes emitting alpha and beta are slowly decaying and
transforming into isotopes emitting gamma radiation. This is why old lenses
can become dangerous after 40-50 years.

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newsbinator
For the non-physicists, how worrisome is this?

In other words, how does this compare to eating bananas, getting dental
x-rays, etc?

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floatingatoll
It's not. The XKCD is pretty solid, but if you like napkin-math, here's some.
This is napkin-math quality only. I take no responsibility for personal
irradiation choices.

[http://articles.adsabs.harvard.edu//full/1988JBAA...98..309F...](http://articles.adsabs.harvard.edu//full/1988JBAA...98..309F/0000310.000.html)

Someone studied this back in 1988 and, if I read this right, if you're using a
radioactive lens as an eyepiece (say, for a telescope) then the exposure limit
for the eye back then was a cumulative 15 mSv per year.

This camera emits (rounding up) 0.003 mSv/h, so you must only use it for 5000
hours per year. There's 8760 hours per year, so in order to reach the 15 mSv
annual exposure limit, you'd need to hold this camera up to a single eye for
~13 hours a day for 365 days in order to reach annual exposure limits.

TLDR: If you tape this camera to your skull in front of one eye for a year
including while sleeping, you'd receive 26 mSv of exposure in that eye,
exceeding the 1988 annual safe exposure limit of 15 mSv cited in a random
paper from 1988. Most people will hold the camera up to their eye for less
than this amount of time per year.

TLDRTLDR: Do not use this camera as a cyborg attachment and you'll be fine.

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Daviey
2.7? Not Great, Not Terrible.

