Guide for Engineers
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How I survived the Accreditation of testing laboratory
Please acknowledge beforehand that this is just my experience.
In two chapters.
Chapter 1. About documents
1. First you need to arrange a small meeting for the colleagues, who will work in your testing laboratory. The number of colleagues should be established from the start. Or preparation of the documents would be infinite. Tell employees that 3-4 months before obtain recognition by the ISO/IEC 17025 and 3-4 months after the recognition will be really hard. Once more it will be difficult during the first external audit. (External auditors frighten staff :)
2. You have to understand that you need to write such procedures daily activities of the laboratory, so you can always find all information about the progress of each contract. It seems impossible...
3. To not be afraid, I took a list of the necessary procedures
Also I found the internet texts of procedures. They were poorly written. But it was a good building material for me. You need to find procedures, together with the schemes. It is possible. May You find in other languages. And translate. Make code of procedures as chapters in ISO/IEC 17025 for example:
PSQ-44-01 Procedure for Contract Review
03
04
05
4. My system consist 28 procedures. After my hard work (2-3 months) I improve all bad procedures which I find in internet. And wrote another 9 procedures.
5. At the same time, I prepared forms. Many are journals, which include information about the works during testing of production . The biggest problem - to force myself and colleagues to fill in these journals. It is a terrible work. And not interesting. Colleagues, I explained that if you do not, then we will lose the accreditation and will be non-competitive. I made 25 forms.
6. Gradually prepare procedures and forms. Gradually, the You with colleagues acted first on one procedure that was ready. Then two procedures. And all had to learn to do according of procedures. Someone forgot, someone did not know, someone nervous. You must smiling :)
But gradually, it is not as heavy as the spill immediately 25 procedures. It would be a collapse of the lab for a few weeks.
7. Do not scare colleagues by Guidance on quality. Write to start one procedure that you like. I like Procedure for Contract Review.
Initially (6 months), your colleagues do not see any sense in this paper carousel. Sometimes I do not see any reason to record and store as much unnecessary information. But only a few can keep it in memory. For example you or I, or an experienced manager. And why all this in mind specialist ultrasound? Not everyone is a good memory. So we have to do everything in accordance with ISO/IEC 17025.
Come on!!!
Next Chapter II about technical side of this problem. Will be soon.
Hydraulic test
Crack started in heat affected zone weld of reinforce. Fast cooling prodused brittle structure (see fracture, like after hardening). The picture shows brittle fracture, the fracture likely occurs due to unsuitable phases in welding zone, HAZ and vicinity of weld line, may be the reinforcement plate is not big enough and PWHT is not applied well. Repairing impossible:) But looking at what pressure...
Photo: by AHMED BOUDCHICHE, CHEF DE CHANTIER INDUSTRIE chez CHARCOMEM
How you can calculate x-Ray exposition dose
My colleague Michael got in trouble and sent this message:
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I was working alone with RT lamp I was after night in job, very tired. Problem is i went on exposition, I have not seen that lamp is working my signaliser was very silent. My mistake my fault.
Main question is how much mSv could i get.
Parameters are below:140 kV; 3,2 mA of direction X ray (ERESCO 300 MF4-R) focal lenght 900 mm; time was about 40 s of my being not directly on beam. I was walking and change negative so I was close, collimator was on the level my calf but i had bend down. I am man 90 kg 186 cm. After 30s to 40 s I saw that lamp is working and I run away. I had dosimetry cassette so after 3 months i will know how much I got but i am little nervous. I dont know if should I be stress ( about health or work)?
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You can calculate the worst result, and then refine the result.
Imagine that all the energy is converted into the energy of the radiation, the efficiency of 100%.
E=140 kV * 3,2 mA * 40 s = 17920 J (Joule)
Now you have to calculate the specific energy of the radiation on the distance at which you stayed longest near the lamp.
Eo = E / S (area square meters of sphere with radius - distance where you stayed)
I mean, distance was 1m, R = 1m
S = 4 * Pi * R*R = 4 * 3,14 * 1 * 1 = 12,56 sq. meters.
Eo = 17920 / 12,56 = 1427 J - energy per 1 sq.meter where you stayed.
Area of your body front is appx. Mosteller, 1987 formula (90 kg 186 cm)
S (all area) = 2,16,
S (one side) = 2,16/2= 1,08 sq/.meters
E (You max catch) = Eo * S (your one side body) = 1427 J * 1,08 = 1541 J.
1541 J - dose on your body, BUT -----
Parts of your body absorb radiation differently.
20% (testicles) - 5%(more others) Average - 10%.
You absobed average: 1541*10% = 154,1 J
If all current energy transform in x-Ray, BUT -----
Efficiency current energy transform in x-Ray is not 100%, but 0,2-0,05%
the worst result for you - 0,2% (more energy transform to x-Ray)
this way, you recieved not 154,1 J , but less
154,1 J * 0,2% = 3 J
3 J per all your body, but your wight is 90 kg.
3J / 90 kg = 0,034 J/kg = 0,034 Gr (Gray)
We calculated, that only 20%-5% energy transformed to x-Ray.
This way we can compare this energy with Norm - 20 mSv per year.
So, you could catch 34 mSv for one exposition...
BUT -----
radiation is non-evenly distributed, with a maximum of focus.
I mean, you have passport for x-Ray lamp.
There is chart of distribution x-Ray dependly of squint angle of main direction.
(directional chart)
I mean, less than 50% direct aside of focus.
So, you catch 17 mSv for one exposition, and you can calculate
better if you try to make x-film, when film not in front of focus, and in the side where you stayed during accident.
Measure density of film and calculate, what is efiiciency x-Ray on your direction.
34 mSv * efficiency = less than 17 mSv.
FINAL
Worst result for
Parts of your body absorb radiation differently.
We count that average 10%. In two times more 20% (testicles).
17 mSv * 2 = 34 mSv
Not good!
The total time of sperm maturation lasts up to 70 days.
After exposition You sure got sperm DNA damage.
After 70 days you need in ivestigation DNA quality of sperm.
And you also need in monitoring of thyroid gland, I think 2 times per year.
Monitiryng "bad" birthmarks also.
For other parts of body exposition is not critical.
I took into account the strict parameters that the worst-case.
Use as manual and example!
If you could to know some information, could calculate by yourself using proportion.
1. Coefficient energy transform for this lamp. See passport. I use 0,2%, and exist lamps with coefficient 0,03%. Proportion: (17 mSv/0,2%)*0,03%=2,55 mSv!!!
2. Directional chart of x-Ray device. I mean, less than 50% direct aside of focus, but I maked experiments with lamp made in 1963-1970, wich made 40 years ago. With bad chart of distribution x-Ray dependly of squint angle. New lamps are better, for example I have found directional effectivity in direction 30o less than 15%.
(17 mSv/50%)*15% = 5,1 mSv and took in account 1.
(5,1 mSv/0,2%)*0,03% = 0,765 mSv.
3. I have found, that during gastric fluoroscopy in 1980-1995, patients catch
150-50 mSv. For one exposition.
Exist uncertainties of cancer risk at doses less than 50 mSv, patients undergoing laparoscopic bariatric surgery may receive radiation doses from postoperative diagnostic imaging tests that increase their lifetime cancer risk.
I think, that you will continue your career in RT, but next 1-2 months make monitoring your some health options.
Good luck, Michael!