<P> Portable instruments are hand - held or transportable . The hand - held instrument is generally used as a survey meter to check an object or person in detail, or assess an area where no installed instrumentation exists . They can also be used for personnel exit monitoring or personnel contamination checks in the field . These generally measure alpha, beta or gamma, or combinations of these . </P> <P> Transportable instruments are generally instruments that would have been permanently installed, but are temporarily placed in an area to provide continuous monitoring where it is likely there will be a hazard . Such instruments are often installed on trolleys to allow easy deployment, and are associated with temporary operational situations . </P> <P> In the United Kingdom the HSE has issued a user guidance note on selecting the correct radiation measurement instrument for the application concerned . This covers all radiation instrument technologies, and is a useful comparative guide . </P> <P> A number of commonly used detection instrument types are listed below, and are used for both fixed and survey monitoring . </P>

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