A visitor looked up “How to calculate gross and net weight for IMO dangerous goods declaration?”

IMDG Code does not ask for weight but ask for mass of the goods.

The weight of an object is a measure of the force exerted on the object by gravity, or the force needed to support it. The mass of an object is a measure of the object’s inertial property, or the amount of matter it contains.

Watch difference Between Mass, Weight, and Density

• Gross mass = mass of empty packaging + mass of the cargo
• Net mass = mass of the cargo only

Example an empty drum having a mass of 10 kg is filled with 90 kg cargo

• Gross mass = 10 + 90 = 100 KG
• Net Mass = 90 KG

In IMDG Code whenever the mass of a package is mentioned, the gross mass is meant unless otherwise stated.

In dangerous goods declaration the quantity of dangerous goods must be included in gross mass or volume as appropriate

1. Class 1 Explosives = net explosive mass
2. Empty uncleaned packagings = not required (but carriers will insist some value as their software will not allow empty field)
3. Salvage packagings = an estimate of the quantity
4. Tank container = cargo mass (The mass of containers or tanks used for the transport of goods is not included in the gross mass).

The number, type and capacity of each inner packaging within the outer packaging of a combination packaging is not required to be indicated but carriers may insist.

Mass of the pallets and dunnage or empty CTU must not be included, this will be calculated in VGM. See boxes 18 and 19 of dangerous goods declaration.

IMDG Code mentions weight when batteries are over stacked that the terminals shall not support the weight of other batteries or materials packed with the batteries and for package stacking tests.