12.7 Instruments for Detection and Measurement of Radiation
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grated dose. The greatest advantage of these chambers is that they can be read daily
or even for a short period. The scale gives the dose-rate in rads. This instrument is
often used while dispensing a radioactive material.
12.7.3 Photographic Film Badge
A photographic film badge consists of a small film enclosed in a paper, in a holder. The
accumulated dose in a given period can be estimated by comparing the exposure of
the film with a standard film. Each individual working in the radioactive laboratory
should carry such a film badge. Persons working with softer radiations, such as
β-particles, should wear a special type of film badge, which is sensitive to weak
radiations.
12.7.4 Monitors for Survey Work
A common form of survey monitor is the Geiger counter, connected with a long
coaxial cable to a rate-meter plus a speaker. This type of counter is designed to give
the average count rate on the scale, as well as make a sound, according to the amount
of radioactive material near the counter. This provides a quick method for monitoring
the laboratory and apparatus, as well as for indicating the background level of activity
present in the laboratory. Such type of monitors are usually kept near the entrance of
a radioactive laboratory, so that level of activity can be immediately noticed. This is
very useful, especially if someone contaminated with radioactive isotopes passes by
the counter, the level of sound suddenly increases, which warns the person of some
contamination.
12.8 Design of a Radioactive Tracer Suit
A radioactive laboratory should possess all the basic features of a chemical laboratory,
but due to the hazards associated with the radioactive materials, while designing the
radioactive laboratory some of the following care must be taken.
1. The activity must be confined to a particular area and the level of activity should
increase in a specific order.
2. The counting rooms should be situated in the area of minimum background. For
a low level work, a special counting room should be used and be treated as an
inactive area.
3. Outside the active area, there should be a provision for calculating the results,
or for readings etc.
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grated dose. The greatest advantage of these chambers is that they can be read daily
or even for a short period. The scale gives the dose-rate in rads. This instrument is
often used while dispensing a radioactive material.
12.7.3 Photographic Film Badge
A photographic film badge consists of a small film enclosed in a paper, in a holder. The
accumulated dose in a given period can be estimated by comparing the exposure of
the film with a standard film. Each individual working in the radioactive laboratory
should carry such a film badge. Persons working with softer radiations, such as
β-particles, should wear a special type of film badge, which is sensitive to weak
radiations.
12.7.4 Monitors for Survey Work
A common form of survey monitor is the Geiger counter, connected with a long
coaxial cable to a rate-meter plus a speaker. This type of counter is designed to give
the average count rate on the scale, as well as make a sound, according to the amount
of radioactive material near the counter. This provides a quick method for monitoring
the laboratory and apparatus, as well as for indicating the background level of activity
present in the laboratory. Such type of monitors are usually kept near the entrance of
a radioactive laboratory, so that level of activity can be immediately noticed. This is
very useful, especially if someone contaminated with radioactive isotopes passes by
the counter, the level of sound suddenly increases, which warns the person of some
contamination.
12.8 Design of a Radioactive Tracer Suit
A radioactive laboratory should possess all the basic features of a chemical laboratory,
but due to the hazards associated with the radioactive materials, while designing the
radioactive laboratory some of the following care must be taken.
1. The activity must be confined to a particular area and the level of activity should
increase in a specific order.
2. The counting rooms should be situated in the area of minimum background. For
a low level work, a special counting room should be used and be treated as an
inactive area.
3. Outside the active area, there should be a provision for calculating the results,
or for readings etc.