NetCam - Networked Continuous Air Monitor

Features

• Eight DAC-hr detection sensitivity to meet 10 CFR 835 Implementation Guide
• Acute release alarm in as little as six seconds
• Uniform sample deposition for more accurate calculations
• Radon rejection screen and stripping algorithm lowers false alarms and increases sensitivity
• RadNet compliant with optional encryption and authentication
• Fully functional HTTP server allows for easier installation of monitoring sites throughout a network
• Accessible locally through a terminal emulator
• Two PCMCIA slots for optional mass storage or wireless networking
• Spare RS-232 serial port can be used for future expansion
• All analysis and setup functionality housed in an onboard embedded 99 MHz processor:
Chronic alarm based on concentration or DAC-hr
Sophisticated background compensation algorithm
Local and remote audio/visual alarm annunciators
Access codes for various levels of security
Automatic warning for calibrations due
Compensation for temperature and altitude

Description

The NetCAM has been designed to accommodate modern facilities utilizing networking capabilities to monitor airborne alpha particle activity. By combining the CANBERRA Alpha Sentry Continuous Air Monitor (CAM) sampling head with a specially designed external device providing network support, CANBERRA Aquila's NetCAM resolves many of the issues faced by Alpha CAM users today. These include false alarms due to radon sensitivity, personnel safety, operating cost per sampling location, and remote monitoring capability.

The Alpha CAM's sampling head contains a patented diffusion screen that removes up to 95% of the newly formed radon daughter particles from the air. In addition, the spectroscopic algorithm is extremely effective at subtracting out the radon daughter interference from the transuranic region of interest. This physical and mathematical radon reduction increases the sensitivity of the Alpha Sentry, which in turn translates into a lower false alarm rate. The NetCAM takes advantage of state-of-the-art technology by allowing multiple CAM sampling heads (up to four) to be easily monitored from remote networking stations. This not only improves the safety of personnel by enabling a user to monitor a potential leak situation from outside the affected area, but it also lowers the cost per sampling location by sharing the operator resource.

Each sampling head has a two-fold function in the NetCAM system. The first is to collect airborne particles onto an internal filter and detect any alpha radiation present; the second is to determine the occurrence of an acute release. Air is drawn into the sampling head through the radon rejection screen and through the internal filter by way of a vacuum connection. A Passivated Implanted Planar Silicon (PIPS) detector is positioned above the filter to detect alpha radiation. Signal processing electronics and a multi-channel analyzer (MCA) are used to collect and store the alpha spectra. Alpha spectra generated by the MCA in the sampling head are then collected by an embedded PC in the NetCAM via a direct connection to the CAM. The NetCAM reads the spectrum from each sampling head at regular intervals, applies a precise spectroscopic algorithm, and determines if a chronic release has occurred. A sophisticated background compensation algorithm removes background radon interference to reduce possible false alarms and increase sensitivity. In the event either an acute or chronic release is detected, the NetCAM signals an alarm.

In addition to data analysis, the NetCAM provides the operator with a web-based interface, as well as a local VT100^™ emulated console for accessing and configuring parameters. The uniquely designed mini-web server incorporates a dozen Java^™ applets embedded on thirty web pages. This allows easy access to all configuration parameters, as well as providing a convenient monitoring method throughout an entire local area network via a web browser.

An extensive security system ensures privacy and prevents accidental mis-configurations by unqualified technicians. A series of security levels are assigned to the menus, each corresponding to a certain range of security codes. These codes are then distributed to personnel based upon duties performed and therefore limiting access only to those necessary menus.

Wireless networking and RadNet compliance:
Wireless networks are becoming an increasingly popular area in facilities. They allow easy installation of a local area network monitoring system without the need for cumbersome and expensive cabling designs. The NetCAM system has pre-installed device drivers and console menus for supporting 802.11 compliant wireless networks. Each unit also houses a 10Base-T port for easy integration into a wired networking system.

The NetCAM system is also RadNet compliant including protocols, encryption, authentication, and wireless networking. This provides remote monitoring capabilities available only with the NetCAM system. RadNet is an open network protocol for transferring packets on a local area network from radiation monitoring equipment to network hosts. While it is now used primarily for health physics instruments, RadNet's flexibility and strength make it ideal for remote monitoring of nuclear materials. RadNet uses standard internet protocols that can be seen at http://drambuie.lanl.gov/~radnet.