What is the potential for extremity doses in this X-ray exposure incident?

In summary, a research worker is irradiating drug samples in an x-ray beam running at 60kVp with a tube current of 4mA. Despite a faulty shutter, the samples are loaded with the shutter open and are 12cm from the tube. It takes 45 seconds for the operator to align the samples. The potential extremity doses are then calculated without filtration and with 2mm Al filtration, assuming an exposed skin area of 100sq cm. The likely symptoms and prognosis for short and long-term radiation injuries are also considered. In compliance with IRR99, appropriate actions would be taken as a result of this incident.
  • #1
Badgeronimous

Homework Statement


A research worker is irradiating some drug samples in an x–ray beam.

The tube is running at 60kVp with a tube current of 4mA.

Although the ‘shutter open’ lamp is extinguished, indicating the shutter is closed , it is faulty and the researcher loads his samples with the shutter open.

The samples are 12cm from the tube and it takes the operator 45 seconds to align his samples. Calculate his potential extremity doses assuming

(a) no filtration and
(b) 2mm Al filtration.

Assume area of skin exposed to scattered x-rays is 100sq cm.

What are the likely symptoms for the potential skin dose received and the prognosis for short and long-term radiation injuries?

What actions, in compliance with IRR99, would you take as a result of this incident?

Homework Equations


Attached in solution - I do not have appropriate textbook.

The Attempt at a Solution


see attachment

-----
Hi there, I am a Radiation Protection Technician working in Nuclear Power with no experience at all of X-Rays. As part of a Professional Development course I am doing, I have this question - it isn't really relevant to my work but it is part of the course regardless. I don't have access to an Academic Library and I am severely struggling to find appropriate text to help me answer this question (any texts I have all relate to Nuclear Power, not X-Ray sets). I feel I have probably approached the question incorrectly making it more complicated than it needs to be.

I'm looking to be pointed in the right direction with some links to referable material. I'm absolutely fine with the latter part of the question, it is just the actual calculation of the dose received to the extremities I am having difficulty with. I can see that the dose to the extremities is likely to be very high, in the order of several Sieverts.

Any hints, or links to similar problems that will give me appropriate information will be greatly appreciated.

Thanks
 

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  • #2
Well, you have large parts of the solution attached already. What exactly is unclear?

0.047% should be 4.7% or 0.047, but the following line uses the correct value again.
 
  • #3
Thank you for your reply.

The issue is that I'm struggling on how to make the step from joules to grays.

The course isn't particularly well planned in that regard, I'm given no access to a library or detailed enough study material. I've spent quite a bit of time going over all the material given and cannot find a list of the formula or text relevant to this question, I can't really find anything in my (3rd party) textbooks either - but they all relate to nuclear power, not X-rays. Filtration also will add another facet that has not been covered with the notes I've been given. TBH, the rest of the course has been fine, but I feel this question is almost an afterthought.

I can tell the dose is going to be very high, I suspect it is going to be beyond a threshold that is going to cause local radiation injury - but can't quantify it into grays without knowing the mass deposited into. 1Gy is 1J per KG of a material. All I can see is 0.81J deposited over 100cm2 and I need help getting to the next step.

If somebody can point me to a book, or online resource where I can get the relevant information. I work in nuclear power, but the people at work don't really deal with X-rays and I'm googling for things I can't find or even know exactly what to look for.

A worked example for instance would be brilliant.

Thanks
Alex
 
Last edited by a moderator:
  • #4
Hi,
for a X-rays generator (60 kVp) it comes:
with no filtration 155 mGy/mA/min at 1 meter
with 2mm Al 4 mGy/mA/min at one meter
so at 12 cm and 4 mA it comes:
43 Gy/min (no filtration)
1.1 Gy/min (2 mm Al)
these results come from the book's abacus "Applied Physics of External Radiation Exposure: Dosimetry and Radiation Protection, Springer, 2017"
http://www.springer.com/us/book/9783319486581
Calculations are not so simple because of the continuous Bremsstrahlung spectrum on which is superimposed the tungsten characteristic X rays,
PSR
 
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Likes Badgeronimous

1. What is X-ray radiation and how does it affect the human body?

X-ray radiation is a type of electromagnetic radiation that has a shorter wavelength and higher energy than visible light. When exposed to X-rays, the atoms in our body can be ionized, which can damage our cells and DNA. This can lead to various health effects, ranging from mild skin burns to more serious consequences such as cancer.

2. How is X-ray dose measured?

X-ray dose is typically measured in units of gray (Gy) or millisieverts (mSv). Gray is a unit of absorbed dose, which measures the amount of energy deposited in a specific mass of tissue. Millisieverts, on the other hand, is a unit of effective dose, which takes into account the type of radiation and the sensitivity of different organs in the body.

3. What factors can affect the amount of X-ray dose received?

The amount of X-ray dose received depends on several factors, including the type and duration of the X-ray procedure, the distance between the X-ray source and the body, and the thickness and density of the body part being imaged. Additionally, the age and size of the individual, as well as their medical history, can also affect the amount of radiation they are exposed to.

4. What are the potential risks of X-ray exposure?

Potential risks of X-ray exposure include skin burns, radiation-induced cancer, and genetic mutations. However, the risk of these effects is relatively low for typical diagnostic X-ray procedures. It is important to balance the potential risks with the benefits of the X-ray procedure, as X-rays can provide valuable information for diagnosing and treating medical conditions.

5. How can X-ray dose and injury be minimized?

To minimize X-ray dose and potential injury, it is important for medical professionals to use the lowest dose of radiation necessary for the specific procedure. They can also use protective equipment, such as lead aprons, to shield the body from unnecessary exposure. Patients can also communicate with their healthcare providers about their concerns and ask for alternative imaging techniques if possible.

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