Description Volume Calculation Formula: Hoppus – net mid girth x net mid girth x net length / 16. Allowance: 6 cm on mid girth and 5 cm on length. Length Requirements Minimum acceptable average length per container payload: 6.5 meters. No logs shorter than 5.0 meters to be loaded. Average Girth Per Container 60-69 70-79 80-89 90-99 100-109 110-119 120-129 130-139 Payloads in 40’ Container Approximately 16.5 cbm net / 19.5 cbm gross.