Document Details

The Particle Problem (Progress Report #4)
Subject Terms:
Health Physics; Particles; Sampling; Stack
Document Location:
DOE INFORMATION CENTER 1 Way, Oak Ridge, TN 37831; Eva Butler; Phone: 865-241-4780; Toll-Free: 800-382-6938, Option 6; FAX: 865-574-3521; Email:
Document Categories:
Health, Safety and Environment\Public Health and Safety
Document Type:
Publication Date:
1949 Mar 07
Declassification Date:
1979 Jun 26
Declassification Status:
Document Pages:
Accession Number:
Document Number(s):
ORNL 319
Originating Research Org.:
Oak Ridge National Laboratory
OpenNet Entry Date:
1995 Mar 10
The third report covered particulate sampling through November 9, 1948. This report records sampling data through January 31, 1949. During this period the filter house was connected into the pile exit air duct and put into operation. This entailed a pile shut-down of several days while the ducts were broken through and connected, and also the blowing out of the contaminated concrete dust, pulverized in the course of the operation, from beyond the exit side of the filter. The period also includes two RaLa runs. Collection data from 3' x 4' sedimentation frames are shown in tables. While these collections are not a measure of breathable particle sizes, they do give an indication of the comparative density of paraticulate contamination - at least as regards solids, such as are produced in the pile. They have been found not to be an indication of chemical-process produced contamination, which presumably occurs at their sources in the form of a fine mist. Allowing for the above limitations and the fact that frequent and heavy rainfall throughout the period interfered with collecting efficiency, data indicates that a considerable number of pariticles of contaminated concrete, shattered by the break-through, was vented through the stack immediately after the filter-house was put into operation. This was expected; however, it was somewhat surprising to find that the particles continued to apear in some profusion for many weeks. Data shows that more than a fourth of the particulates collected in the September-October period were due to relocation, that the cleanup of the plant area (grassing, paving, etc.) was effective, that a large number of active particles were produced during the duct break-through, that the filter system brought about a sizeable dimunition of the number of heavy particles, and that collection rate during January was about one-fourth that of the period of total shut-down in October. It is noted that Frame #11 is on the roof of the fan house and is perhaps the most significant as a measure of the primary source; and #13, which gives the highest recent values, is near a concrete walk which was not affected by the paving and grassing operations and consequently, may be a secondary source. In considering all the data pertaining to the January RaLa run, the activity is all concentrated in a very small area around 706-D; and the collections by both the filtron and the USPHS filter are higher than that of the stack sample. Both of these phenomena point to the building rather than the stack as the chief source of active particles. Particles from a 50-foot stack would show a greater concentration at some distance rather than near the base, and at any rate, would not tend to concentrate the effluent at one spot.

<< Return to Search Results