Bladewerx - Model EpeeBZM -Breathing Zone Monitor

The flexible design provides a high performance platform for detecting trace amounts of radioactive particulates in the presence of ambient radon or alternatively for making high accuracy radon measurements.  The EpeeCAM can be configured to measure and alarm on the presence of special nuclear materials (SNM) or to report on potential alpha energy concentration (PAEC) in working levels.

The EpeeBZM is small enough to be worn inside worker’s anti-C Level A suits. The close proximity of the sampling head to the wearer means much more accurate worker dose assessments than larger CAMs.  Having a size less than 6” x 5” x 3” and weighing a mere 2 pounds, it can be located virtually anywhere.  The EpeeCAM is designed and built to survive the rigors of industrial use.

General Features
The EpeeCAM is a fully standalone battery-powered CAM with audible and visual alarms as well as voice output for alarms and data reporting. Measurements are made using a solid-state alpha/beta detector viewing a filter in the flow path of the built-in 6 LPM pump. The internal Windows-CE processor board analyzes the data from the alpha multi-channel analyzer and gross beta channel and performs alarm determinations and data reporting. Complete log and spectral data can be retrieved from the unit by connecting a USB memory stick or by syncing to a laptop, tablet or PC. Calibration and setup are via PC connected to the mini-USB “client” port. All necessary software is provided with the unit. The EpeeBZM has the optional umbilical that allows the sampling point to be located remotely. The built-in rechargeable lithium-ion battery provides for 8-hours of continuous operation away from any electrical power source. When plugged into the supplied 12V AC adapter, it can be run continuously.

User Interface & Remote Monitoring
Operation of the EpeeCAM is simple and intuitive, requiring no specialized knowledge. Pressing the ON button turns the unit on and monitoring begins immediately. Nothing else is required of the user. Other controls available include volume controls for the speaker and the alarm acknowledge button. The status of the instrument is displayed through the illumination of the alarm, normal or trouble LEDs located on the top and front panels. Voice output of dose and status changes through the EpeeCAM speaker or included ear bud allows for hands-free monitoring, permitting the instrument to be worn on the inside of protective garments. With the 802.3 Ethernet RadNet Output or the Wireless 802.11g RadNet Output Option installed, multiple EpeeCAMs report their status and readings to a local area network where a local laptop or PC workstation running Bladewerx RadNet Client software or other RadNet compliant client software provides remote supervisory monitoring, in real-time, of up to ten instruments.

Radon Mode
The EpeeCAM may be configured to operate in a ‘Radon Mode’ where the instrument will monitor the potential-alpha-energy-concentration (PAEC) of airborne radon and thoron progeny. Because the alpha peak-fitting algorithm separates out the individual activities of 218Po, 214Po and 212Po, the 214Pb and 212Bi beta contributions to PAEC can be determined. This allows for an exact solution for PAEC since all the individual activities of the alpha and beta decay products are known. The display units can be configured for either units of milli-Working Levels (mWL) and WL-h, or SI units of µJ/m³ and µJ-h/m³. Because the individual progeny concentrations are known, the effective (dis)equilibrium ratio of radon progeny can be determined and displayed. This feature can provide useful insights into the ‘age’ of the air sampled. Further, the beta channel is used to determine the RaB (214Pb) contribution to the PAEC, making this an extremely accurate radon monitor with a sensitivity of under 1 mWL.

Sensitivity and Response Time
The sensitivity of the EpeeCAM for measuring and alarming on specific isotopes of interest in the presence of a radon background is dependent on several factors including the radon background, dust loading, sample flow rate, count time settings, and, of course, the energy of the isotope of interest. The count data are analyzed simultaneously with two different user-settable count times, the shorter one referred to as “Acute” and the longer referred to as “Chronic”. In a radon background of ~2 pCi/L, a minimum detectable dose (MDD) of less than 2 DAC-h is achievable with Chronic count time of 4-hours. A simultaneously running Acute count time of 2 minutes achieves an MDD of less than 100 DAC-h.

Data Logging
The EpeeCAM creates log files of both the Acute (from 1 to 30-second detail) and Chronic (1-minute detail) readings, along with spectrum log files at a user-defined interval. These log files may be saved in the internal memory or on a removable SD memory card for later retrieval and review. The log files use the comma-separated-variable (*.csv) format, recognized by most spreadsheet and database software.