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Monitoring for airborne radioactivity is an important function in the health physics and environmental safety workplace. Air samples are often collected using an air pump to draw air through sample media, which is removed and placed in a counting system. Airborne activity is calculated based on the air volume drawn through the sample media and the activity measured on the media. For the process to work, the air volume must be accurately measured, the air flow data and collection data must be accurately recorded and transferred to the counting system. In practice there are factors that make the task time consuming and prone to errors.
In practice, air sample volume is often calculated based on the starting and ending flow rates through the filter. The calculation is based on the rate of reduction in air flow through the filter, due to loading of particulate matter on the filter itself. In a highly controlled environment this assumption is reasonable. In uncontrolled environments, (outdoors, industrial areas, e.g.) the assumption is incorrect, due to rapid and unpredictable changes in the particulate load in the air. TRAC eliminates the environmental variables from the calculations. It also eliminates the need for hand transcription of all collection data. Some over-engineered require expensive sample media as well as extensive personnel training and procedure changes. The same systems also require expensive software licenses and maintenance contracts if support from the factory is expected. Protean Instrument's TRAC system requires no contracts, expensive media, extensive training, or procedure writing. Protean Instrument Corporation’s TRAC system fits transparently and inexpensively into today’s air monitoring program.
TRAC (Totalized Retentive Air Collection) lets you place inexpensive sample media quickly and easily. Any filter media that is available in 2 inch diameter can be used. TRAC accurately measures total air volume drawn through the media. TRAC continually records collection data to the media carrier. The TRAC carrier automatically transfers collection data to the analytical system. TRAC works through a combination of well proven technology. Air flow in a TRAC air pump is measured using calibrated mass flow. Regardless of barometric pressure, temperature, or filter loading, the TRAC sensor will accurately measure and record the total air volume drawn through the filter.
Data collected by the TRAC controller is recorded on a durable “button” memory device permanently mounted to a sample carrier. Button memory devices are widely used in industrial applications requiring environmentally sealed, uniquely coded, and tamper proof data storage. Each button memory device has a permanent serial number that is used for part of the sample ID. The TRAC system records the STP corrected air volume, collection start and stop times, and a pump interruption flag on the button memory. There is no manual data collection or recording.
The collected sample remains in the carrier and is loaded into a TRAC equipped alpha/beta counter. Protean A/B counters with TRAC readers transfer the data from the button memory to the system, which uses the data for analysis and reports. Manual transfer of sample data is completely eliminated. The combination of proven technology and Protean’s consistently superior alpha/beta counting performance provide an air monitoring system with the highest throughput, most reliability, and lowest startup and running costs.
A TRAC system can be configured to match any site requirements - large or small sample load, few or many collection sites, existing pump network, and mixed stationary/portable sampling. Self contained TRAC pumps are available in desktop and wheeled cart models, both with 2 or 4 CFM pumps. A TRAC controller and sampling head can be retrofitted into almost any plumbed-in system, making it entirely usable in controlled areas and office areas.
TRAC sample carriers can be read on three Protean alpha/beta counting systems.
The WPC-9550 is an automatic single detector system with 50/100 sample capacity.
A TRAC enabled WPC-9550 is ideal for sites with a large number of samples
that are routinely counted for times of 30-60 minutes or less. The MDS manual
system, with 4-64 independent detectors is best for sites with many samples
that must be counted for 30-60 minutes or longer. It is also ideal when many
samples must be counted for different count times. The MPC-2000 is a single
detector manual system, and is perfect where a few samples are counted per
week. With the MPC-2000 a TRAC system can be installed at a fraction of the
cost of a typical alpha/beta counter alone.
The benefits of a TRAC system are clear. TRAC is inexpensive to acquire, especially compared to the cost of a conventional alpha/beta counter plus air pump. Sample media is the same used in existing pump heads. Expensive card mounted filter cards are not used. No software license or maintenance contract is required. An operator trained to use a non-automated system only has to be shown how to load a TRAC carrier with the filter media. The same steps “Load, Collect, Count” are used. The error prone and time consuming manual entry and transfer of sample number, time and date of placement, initial flow rate, time and date of stop, and ending flow rate, are not required at all. There is a great increase in data quality, and a great reduction in the time required to collect and process samples and the data.