© Infrastructure Health & Safety Association (IHSA)
40 • Institute for Work & Health (IWH)
Example 4
Calculate the weight of the steel plate.
Step 1: Complete the calculation
Volume of a rectangle.
Note: Weight of materials in tables are usually stated in lbs/ft³ or kg/m³. The
steps for calcuating weight are the same for metric and imperial dimensions.
The unit weight factor is different.
Convert inches to decimal feet.
Note: to convert inches to decimal feet,
do inches ÷ 12.
4' 6" = 4.5'
1" = 0.083'
11' 6" = 11.5'
V = L × W × H = 11.5' × 4.5' × 0.083' = 4.29525 ft³
Step 2: Locate the unit weight in the Table 1.2.
Steel = 490 lbs/ft³
Step 3: Calculate the weight.
Weight = Volume × unit weight = 4.29525 ft³ × 490 lbs/ft³ = 2 105 lbs
