Model 940-2 Off-Line Liquid Effluent Monitor
- Universal Digital Ratemeter with dynamic range up to 107 CPM
- Scintillation type gamma detector
- Rugged open frame skid construction for ease of maintenance
- Centrifugal type pumping system
- Class 1E qualification available
The Code of Federal Regulations requires assurance that radioactive materials within liquid effluents do not exceed maximum permissible concentrations (MPC) as set forth in the United States Nuclear Regulatory Commission (USNRC) radiation protection standards. This simply means that any effluent that could possibly contain radioactivity must be monitored. Besides the legal implications, sound industrial hygiene practices require that personnel be protected against the possibility of exposure to excessive radiation from any source. Off-line liquid monitors usually include their own pumping systems to insure a constant flow of effluent through the sample volume chamber with sufficient pressure to return the sample to the process. Off-line effluent monitoring is normally utilized where optimum geometry is desired to gain maximum sensitivity. Scintillation detectors are used because of their sensitivity and reliability.
- Off-line liquid monitor
- Compatible with Model 943 Series detectors and Model 942A Series or Model 960 Series electronics
- Optimum geometry for maximum sensitivity
- High temperature versions available
The sample is withdrawn from the process piping through the customer’s sample line to the inlet of the sampling skid. The sample flows through the heat exchanger (when supplied), then through the sample volume to the pumping system and back to the process pipe. The sample flow rate is indicated by a rotameter and manually controlled by a throttling valve. The detector output signal is transmitted to the Universal Digital Ratemeter which displays gross liquid radiation counts. This ratemeter also provides output alarm contacts for Alert, High Radiation and Channel Fail. A low flow alarm is included on the pumping system control module, with alarm contacts for customer use. The low flow alarm also shuts down the system to protect the pump. Check source actuation is manual from the ratemeter, with alarms muted when in the check source mode.
Model Name |
Description |
| 940-2 | Off-Line Liquid Effluent Monitor, includes: Open-frame sampling skid, with the following major elements mounted, plumbed and wired:Liquid sampler (with detector well), fixed volume, with 4 pi lead shielding, Model 841-334 Scintillation type gamma detector, Model 943-36 Flow indicator with manual flow adjusting valve Centrifugal pump Low flow switch Manual inlet and outlet isolation valves Universal Digital Ratemeters, local or remote mounting, Model 942A-200 Optional heat exchanger for sample cooling is available, if required Optional high temperature gamma scintillation detectors, Models 943-36H and 943-36HT |