An examination of the measured dose rates indicates that the fallout from the first burst peaked

prior to H + 1 hour (0900). The reference dose rate (R1x) for this portion of the fallout would be

100 cGyph. The fallout from the second burst peaked prior to H + 1 hour for the second burst

(1200); thus the reference dose rate (R1y) for this portion would be 219 cGyph minus the

contribution from the first burst. Using the procedure for determination of **n **from a single burst,

calculate the decay exponent **nx **for the first contributor.

T1x and R1x represent the time after burst and dose rate at H + 1 of the first burst (nx). T3x and

R3x represent the time after burst and dose rate of the last reading taken before the pattern is

influenced by the second burst. The symbols used in the equation for the second burst (ny)

represent the H + 1 and last reading values for that burst.

Then R4x (1200) would be 19 cGyph as determined from Figure 6-5 on page 6-11. Therefore, R1y, the

reference dose rate for the second contributor, would be 219 - 19 = 200 cGyph. Calculate the decay

exponent (ny) for the second contributor.

Calculate the total dose rate for 0800 hours 24 hours after the first burst by finding the dose rate

for that specific time for each contributor separately; then add the two values. Use Figure 6-5 on

page 6-11.

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