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EBERLINE THERMO PCM-1B PERSONNEL CONTAMINATION MONITOR -WARRANTIEDPHOTOS ON THESE FULLY REFURBISHED UNITS AVAILABLE SOON MORE INFO TO FOLLOW IN FINE WORKING CONDITION - DELIVERED with WARRANTY UNIT DESCRIPTION: Eberline PCM-1B Physical Description The PCM-1B is 228 cm (89.6 in.) high by 75 cm (29.5 in.) wide by 112 cm (44 in.) deep. Without any shielding or gas cylinders, the instrument weight is 250 kg (550 lbs). The 15 detectors in the PCM-1B are gas-flow proportional type consisting of a metal housing with a mylar covered window. The hand (palm and back of hand) detectors are 323 cm2 with a 60% open cover, the remaining probes are 503 cm2 with a 54% open probe cover, depending on the installed metal housing. Operational Description Due to the short range of alpha particles in air, PCM-1Bs can effectively monitor only the hands and bottom of feet for alpha contamination. Unlike the HFM-6, PCM-1Bs maintain an activity (dpm) alarm. During calibration, the Master Reliably Detectable Activity (RDA) and a parameter called the RDA Confidence Factor are entered. These values establish an activity that will post an alarm with a specific confidence. The RDA is set to the appropriate HNF-5173/HNF-5183, Table 2-2, limit and the RDA Confidence Factor is set to 1.65, establishing 95% confidence. Like the HFM-6, all PCMs have three operating modes: Preset All (Mode 1), Maximum Sensitivity (Mode 2), and Minimum Count Time (Mode 3). The recommended mode of operation for PCMs within PHMC is Mode 3, with a fixed Master Reliably Detectable Activity (RDA) equal to the facility's HNF-5173/HNF-5183, Table 2-2, total contamination limit. Operating modes other than Mode 3 are used at the discretion, and direction, of facility technical staff. In Mode 3, the PCM computes its count time based on the RDA setting for each channel, a sigma factor (false alarm rate), confidence level, and detector background. Once the constants are entered, the PCM varies its count time with background. While unoccupied, PCMs automatically measure the background count rate. A high background alarm occurs if the background in any channel is high enough that the computed count time exceeds a preset maximum count time. Mode 3 is recommended as the site-wide standard because it minimizes survey times and is more flexible in environments with changing background rates, including fluctuating radon levels. The PCM RDA setting is not an absolute alarm set point (i.e., the RDA represents a probability of detecting contamination at the RDA value). The confidence level entered during the calibration establishes this detection probability. All PCMs within PHMC operate at the 95% confidence level (RDA confidence factor of 1.65). Therefore, PCMs set to alarm at 5,000 dpm 137Cs will detect that activity level 95% of the time. This same instrument alarms on less than 5,000 dpm 137Cs with a reduced probability of detection. As a result, it is not strictly correct to state that a given PCM has a fixed portable instrument equivalent detection level. Instead, PCM alarms are possible, with varying frequency, over a range of portable instrument count rates. This situation is evident when a PCM alarms and subsequent manual frisks fail to find contamination. In this situation, the PCM alarmed at a contamination level below its RDA (a level that portable instruments cannot detect), or the instrument has experienced a false alarm based on the ~0.0 5% probability of this occurrence. Due to the large detector area and the PCM-1Bs channel summing capabilities, these instruments can detect lower levels of distributed contamination when compared to portable instrument capabilities.ALL UNITS ARE GUARANTEED & MAY BE RETURNED FOR REFUND OR REPLACEMENT AT THE DISCRETION OF BUYER WITHIN 30 DAYS OF RECEIPT FOR EVALUATIONMUCH MORE THAN 70% DISCOUNT vs. NEW UNITSALL INSTRUMENTS ARE SUBJECT TO PRIOR SALE AND ARE OFFERED ON A FIRST-COME, FIRST-SERVED BASIS.Stewart Farber [203] 441-8433 [office] email: radproject@sbcglobal.net==================================== TERMS: Shipping and handling costs will be determined based on location of buyer. Unit can be crated and shipped, either domestically or abroad, for a fee based on location. Please e-mail if any questions. Click here to view my other auctions
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