a. Using Figure 3-5, align a hairline from the yield

on the right-hand

scale to the value of the effective wind speed

on the left-hand

scale; at the intersection of the hairline with

the center scale,

read the value of the downwind distance of the

Zone of Immediate

Operational Concern (Zone I) for a surface burst.

Record this value

on **line m **of the worksheet.

b. If the Fission Yield/Total Yield (FY/TY) ratio is known, obtain the

FY/TY adjustment factor from Figure 3-6.

This information along

with the height of burst (HOB) is received from fire direction

personnel for friendly bursts. Lay a hairline from the total yield

on the left hand scale to the value of the FY/TY ratio on the right-

hand scale; at the intersection of the hairline with the center

scale, read the FY/TY adjustment factor. If the FY/TY ratio is not

known, assume the yield to be 100 percent fission and use an FY/TY

adjustment factor of 1.

Record the FY/TY adjustment factor on

c. If the height of burst is known (as in the case of a prestrike

friendly burst), obtain the height of burst adjustment factor for

yields equal to or less than 100 KT or for yields greater than 100

KT.

Lay a hairline from the yield on the left-hand scale to the

value of the height of burst on the center scale; at the

intersection of the hairline with the right-hand scale, read the

height of burst adjustment factor. If height of burst is not known,

assume a zero height of burst and use a height of burst adjustment

factor of 1. Record on **line n **of the worksheet.

d. Multiply the Zone I downwind distance for a surface burst, by both

the height of burst adjustment factor and the FY/TY adjustment

factor to obtain the adjusted downwind distance of Zone I for the

given conditions. Record this value on **line o **of the worksheet.

e. Double the distance found to obtain the adjusted downwind distance

of the Zone of Secondary Hazard (Zone II).