Presentation is loading. Please wait.

Presentation is loading. Please wait.


Similar presentations

Presentation on theme: "TRAINING COURSE ON X-RAY FOR GP"— Presentation transcript:

Venue: ESSET, Bangi Date: 4-9th April

2 INTRODUCTION: X ray was firstly discovered by Wilhelm Conrad Roentgen , a German physicist on 8th Nov 1895 1) Defination: Radiation – a form of energy emitted from a source and propogated through a space either as a wave or particles a. ionizing eg. X ray, gamma ray, beta ray b. non ionizing eg. Microwave, video, visible light 2) The equal absorbed dose of radiation by medium causing harm known as dose equivalent (Sv)

3 After 2 years discovered, 69 cases of skin injury reported due to overexposed to radiation
In 1900, found radiation cause sterility, reduced WCC, illness and death. Comprehensive data obtained from victims of atomic bomb of Nagasaki and Hiroshima

4 Effect/hazard of radiation:
Biological damage: - cell may die - cell changes  abnormal cell divisions - genetic materials of cell may change and passed on to new cell 1)Deterministic effect 2)Stochastic effect

5 a) Stochastic effect: -sometimes effect of radiation is to alter the cee and not affect the cell significantly so no observable effect however might affect the control system divide than normal eg. Ca No threshold ie dose level causing probability of occurrence ( amt of radiation do not change with severity of ca) b) Deterministic effect: - more to effect on the specific organ -severity in individual depend on ionizing radiation dose -Has threshold dose (severity increase with dose) -Effective dose of 50 mSv/yr will cause clinical symptoms - 1shot of xray produces 0.002mSv/xray - x ray operator exposed 2mSv/ year ( limit 2.4mSv/ year)

6 - eg.: erythema or skin reddening
dose below threshold – no symptoms if the dose is increased just above threshold will cause reddening , if dose increased further will cause blister, higher dose will cause death of skin tissue and ulceration

7 The sensitivity of different type of cells in different order

8 Effects of acute whole body exposure to radiation

9 Effects of acute exposure to specific organ

10 Skin effect

11 Effect on eye

12 Radiation protection concept
-objective : to prevent sources of radiation from causing deterministic effect and reduce stochastic effect as much as possible Effect depend on the dose, age, part of body The effect cant be terminated but can control and limit to acceptable level by enforcement of rule and law a) Establish Regulatory Agency for Enforcement : AELB (industry) Ministry of Health (medical)

13 b) Adopt Radiation Protection Standard
Basic Safety Standard (BSS Act 304) c) Local rule 3 basic principles of RP: 1) Justification : no practice shall be adopted unless it process benefit eg medical c/up 2) Dose limitation : dose exposure shall not exceed appropriate circumctance recommended by BSS 3) Optimization : exposure shall be kept as low as reasonable achievable (ALARA) – clothing, monitoring, equipment

14 Optimisation technique:
a) personel protective clothing – lead apron l, lead skirt , thyroid shield, gonad shield b) monitoring – monitored monthly basis . eg film badge, thermoluminescent badge or ring (TLD) , pocket dosimeter administrative control eg local rule, warning sign / light c) choice of technique and working procedure

15 Radiation protection concept:
Exposure: Occupational exposure – radiation recieved by radiation worker medical exposure – radiation received by patient - no dose limit only has guidance level - Dr will determine whether xray is justify 3) Public exposure – radiation received by operator , dr , public

16 Radiation effect on pregnancy staff
female staff: -embryo is radiation sensitive - Once pregnant  should notify to licensee ASAP - limit dose to abdomen 2mSv to ensure fetus not affected ( M’sia dose to feotal <10mSv ) - If the dose restriction is achieved, no special administrative arrangement for the worker is needed - Pregnancy shall no be considered a reason to exclude a female worker from duty

17 - pregnant patient xray should be avoided unless for certain reason
- procedure when patient is found to be pregnant after xray examination: a) estimate absorbed dose to fetus b) consult patient patient about risk - very rare for dose to be large enough to advise patient to consider termination of pregnancy - fetoel dose below 100mGy should not be considered a reason for termination

18 Measures to minimize hazard:
a ) keeping amount of radiation dose required to minimum eg by increase kV , good cassette, 3 phase generator b) choosing the safest and practicable procedure , equipment and cloth (apron , gonad shield) c) only handled by trained staff d) reduce radiation level outside control area

19 Safety measure in exposure room
Person Room- must be approved by the licensing authority specified in the MS838 (1985) a) location and dimension - preferably sited at the ground floor b) material – 2mm lead equivalent, 13mm brick - exposure outside the room < 2.58mSv/week c) window and other opening preferably sliding type - window and aircondition at least 2m above tha floor

20 d) position of apparatus
- do not direct to control panel , dark room, door, window or adjacent occupied area - control panel at least 2 m in Ht and 2m away from table e) warning light - must functiion properly f) dark room - properly ventilated - light tight: should not see outside light at least 5min dark adaptation

21 Equipment X ray system:
- an asseblage of component for the the controlled production of xray -includes: generator , control panel, tube assembly, beam lighting device and bucky Generator: power supply (TNB): 240 volt, 13A , AC power need (X ray ): 20 – 150 k V ,100mA , DC



24 Life expectancy lost due to different causes

25 Comparison of risk; radiation smoking and driving




Similar presentations

Ads by Google