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Training Course on Radiation Safety Awareness - Industrial NDT Consultancy & Training ----------------------------------------------------------------------------------------------------------------------------------------------------------------
IN – HOUSE TRAINING COURSE MATERIAL ON RADIATION SAFETY AWARENESS (Doc. # INDTCT/RSAW/01)
REVISION STATUS Rev. #
Date of Revision
Clause #
Description of Change
Executed by
00
25.06.07 (Initial Issue)
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CONTENT 1.
INTRODUCTION
3-3
2.
NATURE OF PENETRATING RADIATION
4-4
3.
RADIATION QUANTITIES AND UNITS
5-5
4.
BIOLOGICAL EFFECTS OF RADIATION
6-8
5.
RADIATION HAZARD CONTROL
9-11
6.
RADIATION DETECTION PRINCIPLES AND INSTRUMENTATION
12-12
7.
TRANSPORTATION OF RADIO-ISOTOPE
13-14
8.
RADIATION MANAGEMENT SYSTEM
15-19
9.
HANDLING OF RADIATION ACCIDENT / EMERGENCY SITUATION
20-23
Attachment -1 – Safe Handling Instrument Attachment 2 – Transport Index card Figure – Radio-Isotope Storage Pit
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CHAPTER 1- INTRODUCTION The ionizing radiation is hazardous to human body and other animals. It has the ability to damage human body tissues. Commonly radiation hazard is occurring from X-ray generating equipment and radioactive isotope which are used at various medical and industrial fields within our society. Apart from industrial and medical radiation exposure, human being is constantly exposing to natural environmental radiation. Ultraviolet ray and other many radiations are falling on earth penetrating through ozonosphere from space. These are called “Cosmic ray”. There is other natural radiation in the earth besides cosmic radiation. Example, radium is natural radioactive material existing in the nature. Many rocks in the earth are also emitting natural radiation. Human being can’t avoid this natural radiation. This is called back ground radiation. There is a threshold value of radiation level below which it is not harmful to human body. Our intention should be minimize the radiation level as low as possible to reduce the chance of damage. As we are intended to work in radiation field, it is important to us know the ionizing radiation and its effect on human body. Ionizing radiation has the ability to damage human body tissue. Damage to human tissues becomes a problem when ionizing radiation exceeds a certain level. Here we discuss the acceptable and unacceptable limit of radiation level in later in this course material. However, a couple of points to keep in mind in regard to radiation work:
Acceptable limits of radiation exposure have been established to protect radiation workers. One person can perform all his duties and stay within these acceptable limits.
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2. NATURE OF PENETRATING RADIATION 2.1 THE ELECTROMAGNETIC SPECTRUM X-rays and gamma rays differ only in their source of origin. X-rays are produced by an x-ray generator and gamma radiation is the product of radioactive atoms. They are both part of the electromagnetic spectrum. They are waveforms, as are light rays, microwaves, and radio waves. X-rays and gamma rays cannot been seen, felt, or heard. They possess no charge and no mass. 2.2 PROPERTIES OF X-RAYS AND GAMMA RAYS
They are not detected by human senses (cannot be seen, heard, felt, etc.). They travel in straight lines at the speed of light. Their paths cannot be changed by electrical or magnetic fields. They can be diffracted to a small degree at interfaces between two different materials. They pass through matter until they have a chance encounter with an atomic particle. Their degree of penetration depends on their energy and the matter they are travelling through. They have enough energy to ionize matter and can damage or destroy living cells.
2.3 GAMMA RADIATION Gamma radiation is one of the three types of natural radioactivity. Gamma rays are electromagnetic radiation, like X-rays. The other two types of natural radioactivity are alpha and beta radiation, which are in the form of particles. Gamma rays are the most energetic form of electromagnetic radiation, with a very short wavelength. Gamma ray is produced in radio-isotope (Iridium 192) which is placed in radiography camera. Alpha and beta particles are also emitting from radio-isotope along with gamma ray. Alpha and beta particles are maximum hazardous in compare to gamma ray, however, they can travel only few centimeters in air. Therefore they are not dangerous until we touch the guide tube when camera is on. Gamma ray is continuously produced from the radio-isotope whether the radiography work is going on or not. Therefore the radiography camera always be handled with safety and care. 2.4
X-RAY RADIATION
X-ray is produced through X-ray machine either external X-ray or internal crawler. The X-ray machine produces X-ray only when it is connected to power supply and the ‘start’ button is kept ‘on’ but it immediately stops the X-ray emission after the cut off of power supply.
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3.
RADIATION QUANTITIES AND UNITS
Units are necessary for quantitative description of any physical process or phenomena. In radiological physics, units are required to measure a. Radioactivity b. Exposure c. Dose RADIOACTIVITY Radioactivity of a source is measured in terms of the number of transformations it undergoes in one second. The unit of radioactivity is Becquerel (Bq) One Becquerel corresponds to one transformation per second. Formerly, the unit of activity was Curie (Ci) corresponding to 3.7 X 1010 transformation per second. 1 Ci = 3.7 X 1010 Bq = 37 GBq EXPOSURE Exposure is giving the idea about the amount of radiation present at a point of interest. This is basically based on the ability of radiation to produce ionization in air. The unit of exposure is Roentgen or mili-roentgen. More the activity (Ci) means more exposure in a certain distance from the camera and more the exposure means more the radiation hazard. Therefore, for higher activity (Ci) source, more distance to be maintained from the source while the camera is open. DOSE The dose from ionizing radiation is the energy imparted, to matter by the ionizing radiation, per unit mass of the irradiated material at the place of interest. The unit of dose is Gray )Gy) The biological effect of human being depends on dose received by him. The more time exposed to source, the dose shall be received. Therefore, don’t stand near the source unnecessary for long time.
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4.
BIOLOGICAL EFFECTS OF RADIATION
Cells are the basic units of living organisms. All tissues are made of cells. Adult human body consists of about 1014 cells. Cells of different organs carry out the functions specific for those organs. For example, nerve cells are responsible for transmitting electrical impulses from one part of the body to the other; liver cells are responsible for metabolizing the food we take and preparing nutrition for all other tissues in the body; red blood cells carry oxygen and nutrition to all tissues. Cells of different tissues have different sizes and shapes. However, in general, they all contain a central nucleus (with the exception of red blood cell), surrounded by a viscous fluid called cytoplasm. The nucleus contains chromosomes which constitute an array of genes. The chromosomes control all the functions of the cell and hence, of the tissues. The cytoplasm contains various membrane systems and other components that are necessary for the function of the cell. 4.1 CELL DIVISION Cells originate or multiply from preexisting cells by the process of cell division. For example, a human being, like any other animal, develops from a single cell, which is formed by the fusion of two germ cells from opposite sex. During the nine month period of pregnancy, this cell undergoes a number of divisions. The new cells in turn specialized to form various organs of the fetus (unborn baby). After birth, cell division continues until the organ attains adult proportions. Cell in many tissues of the body have life span shorter than that of the body, as a whole. For example, intestinal cells, blood cells, skin cells, etc., have life span ranging from a few days to a few weeks. They wear out and die. They are continuously replaced for the proper function of the tissues. Tissues undergoing cell division are more sensitive to radiation than others. For the point view of radiation hazard, cells can be classified in two groups a) Somatic Cells b) Germ Cells Germ cells are the ones involved in reproductive process. They are sperm in the male and egg in the female. All other cells in the body are somatic cells. 4.2
BIOLOGICAL EFFECTS OF RADIATION
When radiation passes through the body, it transfers some of its energy to the cells in the form of ionizations and excitations, which in turn lead to a number of chemical changes. These chemical changes are harmful to the cells. Depending on the seriousness of harm, a cell either dies or gets modified. All the biological effects of radiation arise from these two effects on cells – Cell death and cell modification. Radiation can cause break in chromosomes. Majority of these breaks get repaired, but certain breaks may lead to loss or rearrangement of genetic material which can be seen under a microscope. Such events are called chromosome aberrations. Biological effects of radiation can be classified into two groups, depending upon the type of cell damaged. They are somatic effect and heredity effect. Somatic effect arise from damage to somatic cells and they occur in the tissues of the exposed person (eg., effects on skin, blood, lung, bone, thyroid etc.). Heredity effects arise from damage caused to the germ cells and occur in the progeny of the irradiated person.
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Somatic effect dose not occur below certain dose. The severity of the effect increase with the increase of dose. The table below shows some of the early somatic effects and their threshold dose. It is generally assumed that the exposure takes place within a short time – minutes to hours (acute exposure). If the doses are protected (chronic exposure), then the threshold doses will be much higher, since the effectiveness of radiation decreases due to the recovery process. SIGNIFICANCE OF DIFFERENT LEVELS OF RADIATION EXPOSURE Dose 1-2 mSv/y (100-200 mrem/y) 1 mSv/y (100 mrem/y) 5 mSv/y (500 mrem/y) 10 mGy (1 rad)
Part of body Whole body
Significance Background radiation level at sea level
Whole body Whole body Whole body
20 mSv/y (2 rem/y) 150 mSv/y (15 rem/y) 500 mSv/y (50 rem/y) 100 mGy (10 rad)
Whole body Eye Partial body Whole body
1 Gy (100 rad)
Whole body
1 Gy (100 rad)
Reproductive system
Limit for non-radiation workers Average occupational exposure Risk of cancer mortality (about 5 per 10000 exposed) Limit for radiation workers Limit for eye lens Limit for skin and extremities Detectable increase in chromosome aberration. No Detectable injury or sickness. Threshold for radiation sickness (Nausea, Vomiting, Diarrhea (NDV) 5- 10% of exposed individual Temporary sterility in men
Dose 2 -3 Gy (200-300 rad)
Part of body Whole body
3-5 Gy (300 – 500 rad) > 6 Gy (> 600 rad)
Whole body Partial body
Significance Threshold for epilation Threshold for induction of cateract. Radiation sickness in most individuals. Early Erythema induction LD 50/60 for human beings Threshold dose of skin erythema. Permanent loss of hair
The threshold dose for early effects are generally, much higher than doses received by persons during normal working conditions, Hence, when proper working conditions are practiced, these effects of radiation do not occur. However, accidents such as holding sources by bare hands, hiding stolen sources in pockets, etc. leading to severe skin burn and tissue damage have been reported. 4.3 LATE SOMATIC EFFECT . Late somatic effect has no threshold value. It may effect in a very low dose, again it may not effect in a high dose. The most important late somatic effect is cancer 4.4 DOSE LIMIT The International Commission on Radiological Protection (ICRP) sets safety guidelines in the use of radiation. The national Council on Radiation Protection (NCRP) defines permissible radiation dose as “The dose of ionizing radiation, that in the light of present knowledge is not expected to cause appreciable bodily injury to a person at any time during his lifetime.” The NCRP defines the maximum permissible dose equivalent man values for personnel exposure. The same values are adopted in both federal and state regulations. Personnel employed in industrial radiography, using modern equipment and safe practices under normal working Doc # INDTCT/RSAW/01 Rev 00
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conditions, should be able to maintain the following dose limit (Ref. APDO HSE Specification Ionizing Radiation SP 1237
Classification Dose Limit (mSv) Maximum annual effective dose received from 20 occupational exposure as a radiological worker Maximum annual effective dose received from 2 occupational exposure as a radiological worker (average period 5 years) (For pregnant radiological workers) Maximum equivalent 2 dose received from occupational exposure during entire time of pregnancy
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5.
RADIATION HAZARD CONTROL
Use of radio-isotope in various engineering field poses external radiation hazard. For radioisotopes, there is a certain amount of leakage radiation coming out of the source housing. Radiation hazard from any radiographic source depends upon a.
energy of the gamma radiation
b.
radiation output
c.
half-life of the radio-isotope
Each radiography source emits gamma radiation of one or more energies. The energy of the gamma radiations emitted by Iridium-192 (Ir-192) is 0.44 Mev. 1 Mev = 1000 Kev
Characteristic of some radio-isotope
5.1
Radiation Source
Physical Form
Half Life
Iridium-192 Cobult-60
Metallic Metallic
74 days 5.3 years
Americium-241
Metallic
432.2 years
Gamma Energy 0.4 Mev Avg. 1.17 Mev, 1.33 Mev 0.013 Mev, 0.059 Mev
Exposure Rate at 1 meter R/h/Ci MGy/h/GBq 0.5 0.12 1.32 0.31 --
85 µSv/ h/GBq
The penetrating power of a radio-isotope depends on the energy of gamma radiation of that particular radio-isotope.
The radiation level at a particular location increases with increase in activity of source.
The radiation level at a location increases as the distance from the radio-isotope decreases. EXPOSURE RATE CONSTANT
Radiation level at 1 meter distance from a source of unit activity (GBq or Ci) is called the Exposure Rate Constant of the source. It is constant for particular source. Radiation level (R/h) at 1 meter from a 1 ci radioactive source is known as the RHM (Roentgen/ Hour at 1 Meter) of source. Radiation output at 1 meter (100 cm) from a given source = Exposure Rate Constant X Activity of the Source
Thus, the radiation level at 1 meter from a 7 Ci iridium-192 source is = 5.2
RHM of iridium-192 X 7
= 0.5 X 7 = 3.5 R/ h
CONTROL OF EXTERNAL HAZARD
The three basic factors by which external radiation hazard can be controlled are a.
TIME
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a.
B.
DISTANCE
C.
SHIELDING
TIME
It is essential from radiation protection point of view, that the time spent near the source of penetrating radio-isotope should be minimum. The radiation dose received by a radiological worker depends upon the total time spent by him/her near a source. If an operator takes one minute while working with a source and is exposed to 10 mR, another worker who takes 2 minutes to do the same job would be exposed to 2X 10= 20 mR. If was taking ¼ minute, he would have been exposed to only ¼ X 10 = 2.5 mR.
LESSER THE TIME SPENT NEAR THE SOURCE, LESSER WOULD BE THE RADIATION DOSE In order to minimize the exposure a. all the operations should be planned in advance b. Only competent persons (Level II) shall handle the camera. RT level I persons shall only assist the radiographer while working. They can operate the crank unit under the direction of radiographer. They will not handle the camera in any circumstance. c. the work may be shear by two or three operators, if the total workload is large. Evaluation of dose received by each operator should be done by using pocket dosimeters, specially during field radiation work b.
DISTANCE
Larger the distance, lesser is the radiation level. The most effective and economical method of reducing external radiation hazard is to increase the distance between the radiation source and persons. MAINTAIN MAXIMUM DISTANCE FROM THE SOURCE OF RADIATION The radiation intensity or radiation level from a given source decreases as we move away from the source. It is governed by the following inverse square law. I1 D12 = I2 D2 Where, I1 = radiation level at a distance D1 meters from the source I2 = radiation level at distance D2 meters from the source. It means, if we double the distance, the radiation level would be one fourth of the earlier level. Example: 192 source?
Determine the radiation level at a distance of 5 meters from a 74 GBq (2 Ci) iridium-
Solve:
Activity of the source = 74 GBq (2 ci) RHM value for iridium-192 = 0.5 R/h at 1 m Radiation level at 1 meter (D1) from a 2 Ci source (I1) = 2 X 0.5 = 1 R/h
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I2 is the radiation level at 5 meter (D2) Since,
1X1
= I2 X 52
I2 = 1/25 R/h = 1 X 1000 mR/ h 25 = 40 mR/ h c.
SHIELDING
When maximum distance and minimum time do not bring down the radiation level to an acceptably low value, materials like concrete, steel or lead are used as a shield between the source of radiation and the operator. SHIELDING YOURSELF FROM SOURCE OF RADIATION The shielding properties of any material depend upon its atomic number and the energy of the incident radiation. Whenever you go for any radiography work, always try to shelter behind a wall or pipeline support or dump of sand etc. It will provide you extra shielding from radiation.
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6.
RADIATION DETECTION PRINCIPLES AND INSTRUMENTATION
In radiography work, three different types of radiation exposure devices are used 1. Film Badge 2. Pocket Dosimeter 3. Radiation Surveymeter In addition to these, a radiation alarm may also used. 1. Film Badge- While working with radiation, wear the film badge. Film badge keeps the record for your radiation exposure. At the end of the month, send the film badge to the head office and take new badge. The exposed badge shall be sent to laboratory for its analysis. By the analysis, it shall be know that how much dose you received in the last month. The lab authority sends the individual dose report in each month. In case any person achieved excess radiation in any month, it shall be understood by the concerned dose report. After knowing the dose report necessary action can be taken. 2. Pocket dosimeter- Pocket dosimeter shows instant radiation exposure. At the time of work, the pocket dosimeter must be worn. Before going to work, set your dosimeter ‘zero’ . While working, check your dosimeter reading in interval. Incase you find any abnormal high reading, tell the level II person who is working with you. He will take further action. After completion of work while you come back to office, please write down your dosimeter reading in “PERSONNEL DOSE REPORT” format. 3. Radiation surveymeter – Radiation surveymeter gives the proper idea of following
Amount of radiation level at a particular distance from the radiation work. It gives the idea that the source is safely reached inside the camera or not after retracting the crank cable.
Therefore, while work at site always keep the surveymeter ‘on’. The most important thing is that, while proceeding towards the camera after the retracting the source back to the camera, take the surveymeter with you. If the source is not reaching the camera, the surveymeter will indicate high reading which in turn safe you from radiation accident. Therefore, always use the radiation detectors as discussed above for your safety. If you work with following the safety precautions as described above, you are completely free from radiation danger.
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7.
TRANSPORTATION OF RADIO-ISOTOPE
(COMPLYING WITH THE REQUIREMENTS OF PDO HSE SPECIFICATION – Ionizing Radiation SP 1237) 7.1
Radioactive material always shall be transported by road and provided by company’s authorized vehicle and personnel
7.2
Make sure that the source is duly contained within the source exchanger (source housing/ camera).
7.3
Confirm that all the locks and pencil arrestors are in proper position.
7.4
Make sure that the radiation symbol on the source housing is in position.
7.5
If the source housing is free from hot spots, place it in the separate small cabin installed at the carriage of the vehicle.
7.6
Close the box and lock it.
8.7
Prior to use for Radioactive material transportation, the vehicle must be approved by Directorate General of Civil Defense (ROP) for carrying Radioactive material.
7.8
The carriage of the vehicle shall be completely covered and facilitated with lock and key arrangement.
7.9
Yellow and black trefoil warning sign shall be displayed on both side and rear end of the vehicle while containing Radioactive material. The warning sign board shall contain other information like the name and contact telephone No. of the custodian, Radioactive material type, activity in Bq. A written warning to keep one meter away from the vehicle shall also be displayed during the Radioactive material content. All the information and warning shall be written in English and Arabic.
7.10
The source movement form shall be duly filled up by RPS or DRSP and arranged to send to contractor’s Safety Advisor at site as well as company’s site supervisor. The information shall be released at least one day in advance.
7.11
The Radiation dose at any point on the outer surface of the loaded vehicle shall be limited to 2 mSv/h.
7.12
The Radiation dose at 1 meter distance from the outer surface of the loaded vehicle shall not exceed 0.1mSv/h.
7.13
The maximum dose rate at the driver’s seat shall be 2.5 Sv/h.
7.14
The personnel when driving the vehicle carrying Radioactive material, shall not be allowed for driving more than 10 hours in a single day. The driver shall take rest after every maximum 4 hours of driving.
7.15
The vehicle shall be fitted with two portable fire extinguishers of dry chemical powder type, two spare wheel / tyre and a tool kit for emergency repair.
7.16
No persons, other than the classified personnel, are allowed during the transportation of Radioactive material.
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7.17
Journey with Radioactive Material always through shortest and safest known route. Stoppage on journey shall be limited to the minimum time necessary for food, rest and refueling.
7.18
While stopping at public palace, a distance of minimum 2 meters from other vehicles shall always be maintained.
7.19
The Trem card should be available in the vehicle while the source is carrying. A copy of the trame card is given in attachment 2.
7.20
For each and every source mobilization , a ‘source mobilization form’ shall be filled up and send to the site in one day advance to inform the mobilization of the source.
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8. RADIATION MANAGEMENT SYSTEM Any institute handling radio-isotope shall meet the requirements of state federal’s rules and regulation (MRME is responsible I Sultanate of Oman) for the
procurement of radio-isotope
storage of radio-isotope
local transportation of radio-isotope
disposal of radiation waste
However, Hitech Inspection Services LLC needs to maintain certain procedures which enlighting to the following points in a minimum 1. Maintaining a log for radio-isotopes with the date of arrival and date of disposal 2. Log for the personnel movement in the site 3. Log for source mobilization 4. Periodic checking of radiation level in and around the radio-isotope storage pit room 5. Ensuring authorization of vehicle for the transportation of the radio-isotope 6. Maintenance of personal dosimeter record 7. Film badge dose record in monthly basis 8. Induction training of the personnel assigned for radiation work 9. Availability of emergency situation handling kits 10. Availability of radiation monitoring calibrated instruments 11. Periodic leakage test (Wipe Test) of Rqadio-Isotopes. 12. Presence of Deputy Radiation Protection Supervisor(DRPS) at individual bases and Radiation Protection Supervisor (RPS) at coast. 8.1 RADIO-ISOTOPE STORAGE FACILITY Different nations are their own regulation and guidelines for the safe storage of radio-isotopes. In general radio-isotope containing cameras are stored in pit room. The pit room is always kept locked. Fencing is made around the pit room with sufficient height to prevent any unauthorized entry to the pit room. The fencing door is also kept locked. The radiation warning symbols are pasted on the fencing wall. Only authorized persons are allowed to handle radio-isotopes in and out the pit room. A source movement log book is maintained by the authorized radiation officer. The construction of radio-isotope storage is shown in the attached figure ( Compliance with SP 1237). 8.2
CONTROL OF MOVEMENT OF RADIO-ISOPTOPE
One deputy radiation protection supervisor shall be nominated in every radiography site. The source movement record shall be maintained by him in source log book format. The total number of source kept inside the pit at present time should be identified in the source log book. Only approved persons are to be allowed to take out the sources from pit room. The pit room key shall be in the custody of deputy radiation protection supervisor. All the storage pit room shall be strictly free from any flammable combustibles, explosives or other hazardous materials. The radiation level at the surface of pit cover and at the fencing shall be measured and recorded in the interval of each fortnight. The radiation level at the fence should not exceed 2.5S/h (0.25 mR/ h) and at the pit surface not exceeding 1.0 S/h (0.1 mR/h).
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9. SHORT DESCRIPTION OF RADIATION WORK Radiation work almost is same as medical X-ray. While a person goes for his medical X-ray test, he is also exposed to radiation but the amount of radiation and the energy of radiation used for medical X-ray are much lower in compare to industrial X-ray. X-ray or gamma ray is used in industrial field for testing the integrity of weld, parent metal or other items. 9.1 GAMMA RAY USE As we discuss earlier, gamma ray emits from a radio-isotope. This radio-isotope is kept inside the camera. Camera is made with high shielding material which keeps the radiation in safe limit while the camera is not ‘on’. The detail sketch of the camera and assemble is shown below.
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9.1.1
THE AREA PREPARATION FOR RADIOGRAPHY
1. First of all the permit shall be taken for radiography. 2. All the persons who are not involved in radiography shall be driven out of the area before the camera took out of the vehicle. 3. The radiation danger boards shall be displayed in enough number in enough distance so that no unauthorized person enters the area of radiography. Doc # INDTCT/RSAW/01 Rev 00
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4. Before carrying the radiography camera from the vehicle, first check the radiation level around the camera by surveymeter. 5. Ensure that film badge and dosimeter are with you. 6. Down the camera from vehicle and keep it the location as per level II technician’s instruction. 7. The crank unit and guide tube attachment shall be done by level II radiographer. 8. As per level II technician’s instruction operate the crank unit. 9. Always keep the surveymeter ‘on’ while working in radiation field. 10. Incase you work at work shop, then cordon off the area before start the work. The distance for cordon off area shall be determined by level II technician. 11. If the work is conducted at night time, enough number of flush lights shall be displayed around the vicinity of work in order to raise awareness among the member of public about the performance of radiation work in that location. 12. Always follow the instruction of level II radiographer. 13. After finish the job, all the things properly take back to the vehicle.
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10.
HANDLING OF RADIATION ACCIDENT/ EMERGENCY SITUATION
Following situations are considered as radiation emergency situation1. lost of camera from vehicle or site 2. lost of crawler tracking (caesium-137 isotope) unit from vehicle or site. 3. The source stuck in the guide tube. 4. The crank unit is detached from the pig tail while source is inside the guide tube. 5. The camera is under fire 6. The camera is fallen down from height (rack) and the source is out 10.1
LOSS OF CAMERA DURING TRAVELLING
Always be very careful while transporting the radio-isotope carrying camera. Don’t park the vehicle in any unsafe location. Always keep the camera inside the small cabinet at rare side of the vehicle. The cabinet and the rare side door shall be kept lock and key so that no person can take the source out from the camera. Inspite of those precautions, if the source lost immediately call the following persons and inform the matter 1. Operation Manager – 99386353 2. Technical manager cum Radiation Safety Officer – 99475861 3. General Manager – 99469622 Parallely search the camera with surveymeter kept ‘on’. If the camera is nearby area the surveymeter will show the radiation indication. Keep in touch with Hitech responsible persons. 10.2
CAMERA IS DETACHED/ SOURCE STUCK INSIDE THE GUIDE TUBE/ CAMERA FALLEN DOWN FROM RACK
If the existing radiographer is not aware of the situation, first the bring the situation in notice. If radiographer is not in nearby, in that case cordon 0ff the entire area in order to prevent t the unauthorized entry. Following the same, inform radiographer so that he can take necessary action to normalize the situation. Don’t directly involved in the rescue matter without the assistance of radiographer.
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Attachment - 1 Monitoring Instrument and Safety Accessories required for Handling Radiation Emergencies in Industrial Radiography 1)
AREA MONITORING a) b) c)
2)
PERSONNEL MONITORING a) b) c) d)
3)
Gamma Radiography Survey Meter MR 4500 Minirad Radiation Survey Meter Radiation Survey Meter – ND 1000S
TLD / Film Badges Pocket Dosimeters (0-2 mSv, 0-5 mSv) Pocket Dosimeter charger Pocket Radiation Alarm
SAFE HANDLING ACCESSORIES a) b) c) d) e) f) g) h) i) j) k) l) m) n)
Lead Container Lead Sheets (5mm thick, 20 x 20cm size) Lead Shots in Cloth Bags (1kg in each bag) Polythene Bags Plastic Containers Remote Handling tong 2m & 1m long Torch light Cellotape Collimator Bolt Cutter Hacksaw Blade Adjustable Plier Screw Driver Other improvised tools as required
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RADIOGRAPHY CAMERA STORAGE ROOM
PLAN OF STORAGE PIT
A. STORAGE PIT B. SETTING OUT PLAN
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C. ELEVATION OF FENCE AND GATE
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Attachment - 2
TRANSPORT EMERGENCY CARD (TREMCARD) DESCRIPTION OF RADIOACTIVE MATERIAL Material Type
:
Ir-192 Radio-Isotope
Container
:
Depleted Uranium Shielded Container
Nature of Hazard
:
Radiation Hazard
Maximum Strength
:
RHM Value
:
0.5 Mr / hr / m distance from 1 ci source
Packaging Category
:
Category-II YELLOW
STEP TO BE TAKEN ON EMERGENCY SITUATION : -The camera to be visually inspected and if it is found intact, onward journey in the same vehicle or another vehicle can be done. -In case of fire, it is to be fought from distance -If the camera appears to be damaged, the radiation level to be monitored. -At least 3 meter area around the radiation source to be cordoned-off. -Note down the non classified personnel who might be exposed and convey the same to the Hitis Radiation Protection Supervisor to the address given below for further action Important Information about Transportation Material Send from: Responsible person to sent the material: Material send to: Responsible person to receive the material: -Telephone & Address for immediate advice & assistance M Contact Person : Contact Number:
Doc # INDTCT/RSAW/01 Rev 00
Page 23