56 CL No. B. Volume Collection Period (tt3x10-5) ppm sr90/106£43 773=P April 4-5, 1955 1,32 8h+ 774=P April 11-12, 1955 1.93 71.5 + 3.3 775=P April 18-19, 1955 2.27 65 + 6 776=P April 25-26, 1955 1,82 22.5 + leh 777=P May 23, 1955 1.34 709 + 52 778-P May lo-11, 1955 1.54 265 + 12 779-P Hay 17-18, 1955 1.37 178 + 16 780-P May 2-25, 1955 1.69 755 + 33 917-P June 16-17, 1955 1.43 710 + hO 918-P August 5-8, 1955 3.0 300 + 20 919-P August 12-16, 1955 heSl uo+h 920=P August 19-22, 1955 3.5 12), + 6 921-P August 26-29, 1955 3.6 226 + 16 922-P September 26-27, 1955 1.53 1568 + 9 923-P September 29-30, 1955 1.69 . - SrSurface Air Concentration, Foreign Locations 124 + 8 NYOO There is considerable uncertainty in tne air volumes of samples collected at Kodiak, T.A., Port Lyautey, F.!i., and Yokosuka, Japan because the flow rate is not directly recorded. For the earliest reports of air filter data for these three locations, the rated flow rate times the total collection period was taken as the collected air volume. Because the flov rate falls off substantially as dust accumulates on the filter, those sam»sles were overestimated in volume and thus the revorted air concentration data vere too low. It is considered that a better estimate of their air volume is provided by the average “lashineton, D, C,. volumes for equivalent collection neriods. On this basis, the relative air concentration data should be considerably improved, although their absolute value mar be in error by as much as 50% or so. All the earlier reported air filter deta for Kodiak, Port Lyautey and Yokosuka have been estimated on this basis, and the new results are presen= ted belo. 8] Pf