X-Ray Question - Page 1
Forum section: electronics / general

author: dexters_lab
author_rank: Unknown
timestamp: November 12, 2013, 10:52:13 am
content: i have a good friend who is currently working in Japan, i wont go into what he's doing etc but he took some picture of an operator x-raying some steel plates that have been welded on an interesting 'rig' outside, i have a couple of questions, maybe someone has some answers...First question is about safety, like is there any evidence of it in these pictures?secondly the magenta fogging on two of the pictures, is this just an odd random optical oddity, or evidence of exposure? I would have expected sparkly grainy noise, but i'm no expert.

author: Psi
author_rank: Super Contributor
timestamp: November 12, 2013, 11:21:54 am
content: LOL, yeah, that has no safety shielding at all.When it comes to the safety of something there's 3 categoriesA) Totally unsafe and may harm someone at any timeB) Safe only when used in a particular way (area cleared of people etc.)C) Safe for anyone to be nearby and incapable of being used dangerously due to interlocks and safety features.If the operator of that device has to be near it when it's active then i'd call it cat AIf he turns it on at a distance, outside a roped off safety area etc, then its borderline cat B as long as those 2 images are not being effected by leaking xrays. If there is xray radiation leaking out in that direction then it's definitely CAT AThere's no way that thing would pass cat C and get any sort of xray safety certification and it's laughable to even consider the questionIt looks like it's part of a larger xray machine that was cut up!Do you know if that control box sits on top of the unit and has the sensor array underneath? Requiring the operator to be using the controls while xraying?Xray machines which use photodiode arrays only need low levels of radiation compared to medical xrays and cannot effect photographic film.They probably would effect the exposure on a digital camera sensor though, so i guess its possible that hazy glow could be from the xrays. However the x-rays exit the generator funnel in a beam which points up. So i find it a bit hard to accept they would emit in the direction of the camera taking the photo.

author: dexters_lab
author_rank: Unknown
timestamp: November 12, 2013, 11:33:48 am
content: i think the control box is a short distance away, i think you can see it in one of the pics.I think there is some shielding, notice the sheet of lead attached to the frame with packing tape?Regarding the imaging, yes i wondered what was recording or displaying the image too because i couldn't see anything in his pics

author: Andy Watson
author_rank: Super Contributor
timestamp: November 12, 2013, 11:38:17 am
content: Quote from: dexters_lab on November 12, 2013, 10:52:13 amYes. There's rope and a sign in the second picture.QuoteUnlikely. I very much doubt that the xrays were active in the third picture. As Psi has pointed out, xrays are very directional, if the operator got caught in any part of the beam, he would be fried .

author: dexters_lab
author_rank: Unknown
timestamp: November 12, 2013, 11:39:58 am
content: Quote from: Psi on November 12, 2013, 11:21:54 amyea as i thought, also given one of the pics is fogged when the operator is right next to the source i would guess it's not on at the time... it must be just a coincidental artifact

author: Psi
author_rank: Super Contributor
timestamp: November 12, 2013, 11:42:03 am
content: Yeah, i agree, probably just 2 badly exposed photos and not xray contamination.

author: Terabyte2007
author_rank: Frequent Contributor
timestamp: November 12, 2013, 11:55:56 am
content: Probably not. X-Rays are forbidden to cross safety ropes!No seriously, the pictures look like optical anomalies. I am an amateur photographer on the side and have quite a bit of gear, and I have seen this before in some point and shoot cameras.

author: amyk
author_rank: Super Contributor
timestamp: November 12, 2013, 12:09:48 pm
content: X-rays follow inverse-square law too so the strength falls off quite rapidly as your distance to the source increases.

author: dexters_lab
author_rank: Unknown
timestamp: November 12, 2013, 02:34:04 pm
content: thanks everyone for the replies

author: Fraser
author_rank: Super Contributor
timestamp: November 12, 2013, 02:55:23 pm
content: Similar unit detailed here:http://www.duwell.net/files/rf-egm_series.pdfIt appears to be a source and film system with the pictured units being the source of X-Ray. there should have been an X-Ray film cassette in use as well.If I had seen that equipment being used on one of my sites, I would have been very concerned if it did not have a VERY large controlled space stand-off from people. I would insist on X-Ray safety monitors, both on the operator and all persons working in the area. Duty of care is all important with X-Rays of the likely levels being used here.

author: John Coloccia
author_rank: Super Contributor
timestamp: November 12, 2013, 03:18:34 pm
content: The "fogging" looks like reflections, as though he'd taken the picture through a car or office window. The rig seems perfectly safe to me. XRays are high frequency mostly go straight ahead. What get scattered quickly dissipates to nothing a short distance away. There's probably a bigger chance of harming your eyes from accidentally looking at the welding arc than there is of getting any appreciable radiation from this gadgetAnyhow, devices like this don't just spew x-rays. They're typically set for a pulse...this much for this long...and it's not just on all the time.

author: G7PSK
author_rank: Super Contributor
timestamp: November 12, 2013, 06:22:49 pm
content: The usual thing when taking X rays of welds is the operator goes behind a lead curtain at some distance from the work piece being tested. Those plates look like they are just test tokens either from a robot or welders being certified and are not the actual work piece itself. When I worked where X rays were being done on welds they were normally done at night when when there was no other personnel other than the X ray operators, come in the next morning and there was tanks with red paint on showing where welds had to be gauged out and redone.From what I can see what is going on in the photograph's looks like safe practice.

author: Kryoclasm
author_rank: Regular Contributor
timestamp: November 13, 2013, 05:11:42 am
content: Quote from: dexters_lab on November 12, 2013, 10:52:13 amColor cast and reflections off a pane of glass.

author: jh15
author_rank: Frequent Contributor
timestamp: November 14, 2013, 01:33:18 am
content: So I shouldn't use this to look at my toes?https://www.google.com/search?q=shoe+store+xray+cam&safe=off&client=ubuntu&hs=zLn&channel=cs&source=lnms&tbm=isch&sa=X&ei=xyeEUujqBIXfkQfr-YDoCQ&ved=0CAkQ_AUoAQ&biw=960&bih=475#facrc=_&imgrc=-M6-XILCl59SzM%3A%3BFaFCjreJLBLNtM%3Bhttp%253A%252F%252Fwww.wired.com%252Fimages_blogs%252Fgadgetlab%252F2010%252F11%252Fshoe.ray_.jpg%3Bhttp%253A%252F%252Fwww.wired.com%252Fgadgetlab%252F2010%252F11%252Fvintage-shoe-fitting-x-ray-machines-will-zap-your-feet%252F%3B660%3B451

author: IanB
author_rank: Super Contributor
timestamp: November 14, 2013, 02:39:44 am
content: The long cable snaking out of view in picture 2 almost certainly goes to the control unit in picture 1 (you can just see it entering under the raised cap to the right of the picture).I agree with the comment that the items being examined look like test pieces of some sort.It is extremely common to require industrial welds on piping and pressure vessels etc. to be X-ray examined to ensure the welds are free of hidden defects. You may think X-rays are dangerous, but exploding pressure vessels make the danger from stray X-rays pale into insignificance. Such welds have to be examined in situ, requiring portable equipment and making enclosed shielding impractical.I don't think there is anything unsafe being depicted here. The Japanese have a much more pragmatic view of safety than, say, the British or Americans (they don't fuss over imagined dangers), but they do take note of real hazards when considering safe working practices.