EVALUATION OF A REDUCED PRESSURE BACKFLOW PREVENTER USING ACTIVATION ANALYSIS

Technical Report · Tue Jan 01 04:00:00 EST 1963

DOI:https://doi.org/10.2172/4710469· OSTI ID:4710469

Baird, Jr., J. N.; Sanford, W. R.; Cristy, G. A.

Despite its advantages of economy and convenience, the reduced-pressure- principle backflow preventer was oniy partialiy accepted as a substitutr for air- gap separation in preventing pollution of potable winter. To evaluate the protection provided by a reduced pressure principle backflow preventer, a unit was tested under the following static conditions; ionic diffusion, lower pressure on the supply side than on the discharge side, vacuum on the supply side, water hammer on the supply side, and water hammer on the discharge side. Using a solution of Mn and K nitrates as a nonradioactive tracer, backflow from the discharge side to the supply side was not detectable by activation and radiochemical analyses having a sensitivity of approximates 0.2 ppb Mn. The protection factor for the device is defined as: P. F. = (Reagent concentration in the discharge zone/ Reagent concentration in the supply zone due to backflow). The minimum protection factor proved in these tests based upon the limit of the sensitivity of Mn analysis is 6.5 x 10/sup 8/. This factor provides a rational basis for inatallation where the concentration of radioactivity or other contaminant can be estimated, measured, or limited. The K analyses also showed no detection of backflow but with a lesser sensitivity. (auth)

• Research Organization: Oak Ridge National Lab., Tenn.
• DOE Contract Number: W-7405-ENG-26
• NSA Number: NSA-17-010515
• OSTI ID: 4710469
• Report Number(s): ORNL-3380
• Country of Publication: United States
• Language: English

Related Subjects

ACTIVATION ANALYSIS
CHEMISTRY
DIFFUSION
IONS
LIQUID FLOW
MANGANESE NITRATES
POTASSIUM NITRATES
PRESSURE
SENSITIVITY
SOLUTIONS
VACUUM
WATER