The manager of a community centre should decide about the location of a propane tank (PT) inside the premises of the community centre. The community centre consists of a playground (PG), a drive-in theater (DT), and a large atmospheric water tank (WT) which feeds the adjacent residential complex. The manager has two options for the location of the PT, locations A and B. The distances between the PT and the other targets are depicted in the figure below.

Given fireball as the most probable fire scenario for the propane tank, the community manager wants to choose the location attributed with the lowest total risk considering the damage to the WT and the death of people at PG and DT.

Below are the characteristics of the PT as well as the WT, PG, and DT:

?The PT contains 1500 kg of propane.

-The volume of the WT is 150,000 m3and is worth $2 million.

-The number of people at the PG and DT are 50 and 120 people, respectively.

-The statistical value of life is $3.5 million.

-exposure time can be assumed equal to duration of fireball

To calculate the heat radiation of the fireball, the manager uses the fireball spreadsheet but toaccount for the spreadsheet's inaccuracyconsiders a safety factor of 1.5. In other words, the intensity of radiant heat calculated by the spreadsheet should be multiplied by 1.5. Which PT location would be attributed to a lower risk?

Tip:

Risk of damage to the WT is the damage probability of WT times its value. Risk of death is the number of dead people times the statistical value of life. Total risk is the sum of these risk values.

WT WT 5 m 10 m PT PT 45 m 10 m 20 m 20 m PG DT PG DT Location A Location B