Model 26-1 Frisker User’s Manual Section 1
Ludlum Measurements, Inc. Page 1-1 April 2017
Introduction
The Model 26-1 is an ergonomic, lightweight instrument, which can be
used for alpha/beta contamination frisking or for measuring gamma
exposure or dose. It features the ability to measure radiation in count
rate, exposure rate/dose, activity rate, integrated exposure/dose, time-
averaged rates, and scaler counts. The Model 26-1 utilizes a standard 15
cm
2
(0.9 in
2
) Geiger-Mueller "pancake" detector, which can detect alpha,
beta, or gamma radiation. Caution is needed when handling the
instrument because of the thin radiation detector's window.
Three modes of operation are available for the Model 26-1 – RATE,
MAX, and COUNT. RATE mode operation will display the current
count, exposure, or activity rate. MAX mode is used to capture the
highest count, activity, or exposure rate detected – useful for finding a
peak rate, or frisking when the display is not visible. Primary and
Secondary Units for RATE and MAX modes can be chosen from cps,
cpm, Bq, dpm, mR/h, or µSv/h. COUNT mode allows the user to
perform a count for a predetermined time. Depending on the Count
Units chosen, the result can be a scaler count (in counts or
disintegrations), a time-averaged rate (cpm, dpm, Bq, cps), a time-
averaged exposure or dose (mR/h, µSv/h), or an integrated exposure or
dose (mR or µSv).
Note: The use of the unit to measure gamma dose or exposure
correctly can be enhanced by using an optional snap-on energy
filter. Without this filter, the energy response of the pancake
detector will over-respond to gamma energies in the 20-150 keV
range. See the Gamma Energy Response graph and more
detailed information in Section 4. Ludlum Measurements
recommends the use of its Exposure Filter 4498-334, or the
Ambient Dose Equivalent Filter 2002-1050.
Sectio
1
To Next Page
Loading...
Need help?
General
