Automated Linearity Testing Dose Calibrator for Hot Cell Programs
Product Introduction
The Automated Linearity Testing Dose Calibrator integrates
linearity verification into routine operations, eliminating the
need for dedicated linearity testing procedures that disrupt
workflow. Regulatory standards (including NRC, IEC, and USP)
require dose calibrators to undergo linearity testing quarterly,
verifying that the instrument's response is proportional to
activity across its entire measurement range. Traditional linearity
testing involves measuring a source multiple times over several
half-lives (taking days for long-lived isotopes) or using
attenuator sleeves (which require handling multiple calibrated
sources). This instrument performs automated linearity testing
during routine dose preparation, analyzing data from patient doses
to verify linearity continuously. The software also supports
accelerated linearity testing using a built-in attenuator set that
inserts with a single motion.
Application Range
The Automated Linearity Testing Dose Calibrator is designed for
nuclear medicine departments that must comply with linearity
testing requirements but want to minimize the associated staff time
and exposure. Primary applications include quarterly linearity
verification for regulatory compliance, acceptance testing of new
dose calibrators, performance verification after repair or
calibration, and inter-instrument comparison studies. The
instrument is equally suitable for high-volume departments (where
automated continuous linearity verification provides ongoing
confidence) and for smaller departments (where the accelerated
attenuator-based test simplifies quarterly compliance).
Performance and Benefits
The Automated Linearity Testing Dose Calibrator offers two methods
for linearity verification. The first method — automated continuous
verification — uses data from routine patient dose measurements to
monitor linearity over time. The instrument's software collects
measurements across the full dynamic range, comparing the ratio of
measured activity to calculated decay-corrected activity for each
patient dose. If the instrument is linear, this ratio should be
constant across all activity levels. The software performs
statistical analysis to detect any systematic deviation from
linearity, alerting the user when significant nonlinearity is
detected. This continuous verification method requires no
additional work from staff and provides ongoing confidence in
instrument performance. For quarterly formal testing (required by
most regulators), the instrument supports accelerated linearity
testing using a built-in attenuator set. The attenuators — lead
sleeves of varying thicknesses — are stored in a shielded carousel
inside the instrument. To perform a linearity test, the user places
a long-lived source (typically Cs-137 or Co-57) in the chamber and
presses "Start Test." The carousel automatically rotates through
the attenuator set, and the instrument measures the source through
each attenuator. The software plots measured activity versus
attenuation (proportional to the logarithm of activity) and
calculates the linearity deviation. The entire test takes under 5
minutes and requires handling the source only once — compared to
traditional decay methods that require days of measurements or
sleeve methods that require handling multiple attenuators
separately. The instrument also supports the traditional decay
method for departments that prefer this approach. The software
guides the user through a series of measurements over time
(typically 2-3 days for Tc-99m), calculates the linearity curve,
and flags any nonlinear regions. All linearity test results are
stored in a database with timestamps, user ID, and test parameters.
The system produces a printed report suitable for regulatory
inspection and can export data for external analysis. For nuclear
medicine departments, the primary benefit is reduced staff time and
exposure for regulatory compliance. The accelerated
attenuator-based test reduces linearity testing time from days
(decay method) or hours (manual sleeve method) to under 5 minutes.
The automated continuous verification method eliminates dedicated
testing entirely, providing ongoing confidence with no additional
work. For radiation safety officers, the comprehensive test records
provide defensible documentation of compliance. The Automated
Linearity Testing Dose Calibrator transforms what is traditionally
a burdensome compliance task into a quick, simple procedure.
