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by 3JPLW 2047 days ago
Especially given this:

> That 1948 study of 43 machines in Detroit showed ranges from 16 to 75 roentgens per minute. In 1946, the American Standards Association had issued a safety code for industrial use of X-rays, limiting exposure to 0.1 R per day.

I'd be curious how much a typical modern dental x-ray emits, but we no longer measure in roentgens these days as we have better measures of the actual dose (sieverts).

3 comments

Modern dental x-rays are basically negligible for most patients, although not for dentists who do them daily, even though they're well away from the beam - which is why they have to hide when they take them.

Less negligible are CT scans, which can expose you to multiples of the average annual background dose in a few minutes.

That's still relatively low level exposure. But there isn't really a safe minimum exposure level, and it's certainly not something you'd want to have regularly.

Aren't CT scans equivalent to about 3,000 chest X-Rays? It sounds pretty bad if you're young.
Not quite that bad. These days a chest CT scan (~7 mSv) is worth about 70 chest x-rays (0.1 mSv).

That's 2 years (CT) and 10 days (x-ray) of exposure to sea level background radiation respectively.

With some hand waving 100 roentgens is equal to 1 sievert
Radiation from x-rays is measured in microsieverts, or less than a single day’s exposure to background radiation

https://www.iaea.org/resources/rpop/health-professionals/den...