© Infrastructure Health & Safety Association (IHSA)
38 • Institute for Work & Health (IWH)
Example 2
Calculate the weight (in kilograms) of the pine lumber.
Step 1: Complete the calculation
Volume of 1 rectangle + 1 rectangle
Lower part V = L × W × H
= 10' × 4' × 3' = 120 ft³
Upper part V = L × W × H
= 4' × 4' × 2.5' = 40 ft³
Total volume = 120 ft³ + 40 ft³ = 160 ft³
Step 2: Locate the unit weight in Table 1.2.
Pine = 30 lbs/ft³
Step 3: Calculate the Weight
Weight = volume × unit weight
= 160 ft³ × 30 lbs/ft³ = 4 800 lbs
Step 4: Convert pounds to kilograms
1 kg = 2.2 lbs
Note: To convert pounds to kilograms, divide by 2.2
To convert kilograms to pounds, multiply by 2.2
4 880 lbs ÷ 2.2 lbs/kg = 2 182 kg