Scanna Msc SCANMAX 25 C, Руководство по эксплуатации и техническому обслуживанию

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INTRODUCTION TO X-RAYS
Radiation and the inherent dangers of radiation have in recent years received much publicity however since
1972 the use of x-ray systems has become commonplace throughout the world particularly at Airports.
Indeed in these troubled times the public and staff demand the level of security provided by these x-ray
screening systems.
The use of x-rays is no more dangerous than a piece of industrial machinery with moving parts, if you put
your hand in moving machinery, such as a guillotine, you may be seriously injured, fortunately this type of
accident is rare, if common sense and safety procedures are implemented.
The same is true with an x-ray unit. Not interfering with guarding or access panels,
NEVER defeating
interlocks and regularly servicing the equipment will provide a high degree of safety.
Contrary to Radioactive Sources the x-rays or Ionising Radiation used in the Scanmax 20 and other
systems supplied by Scanna are non residual. That is the x-rays are produced electrically and as soon as
the power is removed from the x-ray generator there are no x-rays in the system.
The following safety measures and devices are included in the equipment supplied by Scanna MSC.
Low x-ray dose.
X-ray beam limiting.
Interlock system.
X-ray On indicators.
Lead Shielding
In the United Kingdom the requirement is a leakage rate as low as is practicable but in no case to exceed 1
micro Sievert per hour. It is the stated intention of Scanna to provide equipment designed so that irradiation
leakage is zero. The Regulations and the Code of Practice has introduced conditions whereby doses of
radiation can and are maintained considerably below the threshold where the radiation has an detrimental
effect. Indeed it is accepted that by far the largest contribution to population dose is from our natural
background, e.g. radiation from space (300
µ
Sv), Gamma radiation from earth (350
µ
Sv ), internal
radiation from natural radioneuclides in the body.(380
µ
Sv ) and inhaled gases and nuclear fallout (970
µ
Sv). The current safety limit for annual exposure is 5000
µ
Sv
Sieverts rem
0.1 10 1 dental x-ray exposure 5 rem 0.05 Sv
0.01 1 Natural radiation. 200 m rem per year
2,000
µ
Sv
0.001 0.1
0.000,1 0.01 1 Transatlantic Flight 2.5 m rem
25
µ
Sv
0.000,01 0.001
0.000,001 0.000,1
0.000,000,1 0.000,01 Leakage from Scanmax unit
0.000,002 rem
0.2
µ
Sv
max.
0.000,000,01 0.000,001
It can be seen from the above figures that spending every hour of your working life within 1 inch of the
equipment with the x-rays switched on would still not so much as double your annual dose of radiation
accrued simply from being alive.