4
$\begingroup$

I work in a general-purpose, commercial office building where the first floor is dedicated to an x-ray / imaging lab for medical diagnostics. The public lobby of this building is routinely experiencing radiation level increase from 0.10 uSv/h (Background) to 0.96 uSv/h in approximately 20 - 30 second intervals as measured by a geiger counter that calculates uSv/h in 10 second increments. To put it another way, my geiger counter typically reads 0.10 uSv/h, but when walking past the lobby I often see the reading increase to 0.96 uSv/h for several cycles. My assumption is that radiation is leaking from the imaging lab and into the lobby as x-rays are being taken, causing accidental exposure to members of the public (myself included).

Does anyone know if this is to be expected or otherwise have insight into whether or not such relatively small dosages are harmful to the public?

$\endgroup$
1
  • 4
    $\begingroup$ Google suggests the "federal occupational limit" of radiation exposure is 5000 millirem/year, which converts to 5.7 μSv/h. So a level of 0.96 μSv/h (intermittently) doesn't seem excessive by that standard, FWIW. See also the xkcd radiation chart $\endgroup$ Commented Jul 22, 2015 at 4:23

1 Answer 1

3
$\begingroup$

I don't think 0.96 $\mu$Sv/h or 365.25 $\times$ 24 $\times$ 0.96 = 8,415 microsieverts/year is a problem. To put this in perspective,

  • Every year, we receive natural radiation : 2,000 microsieverts
  • CT scan : 7,000 microsieverts
  • Additional radiation in a life time for those living around Fukusima : 10,000 microsieverts
  • US radiation worker in a year : 50,000 microsieverts
  • Astronaut in the International Space Station for 6 months : 80,000 microsieverts
  • In a smoker's lung in a year : 160,000 microsieverts

Therefore, don't worry about the amount of radiation leaking from your lab. It is very very small.

P.S. I get this number from a Veritasium's video called "The Most Radioactive Places on Earth".

$\endgroup$
3
  • 1
    $\begingroup$ Thank you for answering! This is exactly what I was hoping to learn by posting this question and it definitely puts my mind at ease. P.S.: I have upvoted your answer in addition to accepting it, but my reputation has to reach 15 points before my upvote will display. $\endgroup$
    – user86456
    Commented Jul 22, 2015 at 11:51
  • 2
    $\begingroup$ TBBT, did you mix up microsieverts and millisieverts? 365.24 * 24 * 0.96 = 8400, not 8.5... $\endgroup$ Commented Jul 22, 2015 at 19:37
  • 2
    $\begingroup$ @NathanReed Apology for my mistake. Thank for correction. Please edit my answer. $\endgroup$
    – TBBT
    Commented Jul 23, 2015 at 6:27

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.