Design, calibration, and operation of {sup 220}Rn stack effluent monitoring systems at Argonne National Laboratory

Journal Article · Thu Sep 01 04:00:00 EDT 1994 · Health Physics

DOI:https://doi.org/10.1097/00004032-199409000-00013· OSTI ID:54484

Munyon, W J; Kretz, N D; Marchetti, F P ^[1]

---

1. Argonne National Lab., IL (United States)

A group of stack effluent monitoring systems have been developed to monitor discharges of {sup 220}Rn from a hot cell facility at Argonne National Laboratory. The stack monitors use flow-through scintillation cells and are completely microprocessor-based systems. A method for calibrating the stack monitors in the laboratory and in the field is described. A nominal calibration factor for the stack monitoring systems in use is 15.0 cts min{sup {minus}1} per kBq m{sup {minus}3} (0.56 cts min{sup {minus}1} per pCi L{sup {minus}1}) {+-} 26% at the 95% confidence level. The plate-out fraction of decay products in the stack monitor scintillation cells, without any pre-filtering, was found to be nominally 25% under normal operating conditions. When the sample was pre-filtered upstream of the scintillation cell, the observed cell plate-out fraction ranged from 16-22%, depending on the specific sampling conditions. The instantaneous {sup 220}Rn stack concentration can be underestimated or overestimated when the steady state condition established between {sup 220}Rn and its decay products in the scintillation cell is disrupted by sudden changes in the monitored {sup 220}Rn concentration. For long-term measurements, however, the time-averaged response of the monitor represents the steady state condition and leads to a reasonable estimate of the average {sup 220}Rn concentration during the monitoring period. 5 refs., 5 figs., 3 tabs.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• Sponsoring Organization: USDOE
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 54484
• Journal Information: Health Physics, Journal Name: Health Physics Journal Issue: 3 Vol. 67; ISSN HLTPAO; ISSN 0017-9078
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AIR POLLUTION MONITORING
AIR POLLUTION MONITORS
CALIBRATION
DESIGN
HOT CELLS
RADON 220