Dunnage
Dunnage is material used to fill voids, block, separate and protect cargo, such as timber beams, boards, fibreboard sheets and inflatable dunnage bags. Loose cargo can shift under road and sea accelerations; the CTU Code tables cite up to 0.8 g forward on the road. Timber used as dunnage in international shipments must comply with ISPM 15. Make sure airbags do not press against the container doors.
Related terms
- Lashing
Lashing means securing cargo so it cannot shift under the accelerations of a sea voyage or a road journey.
- Stuffing
Stuffing is loading goods into a container, either at the shipper's premises for FCL or at a CFS for LCL.
- ISPM 15
ISPM 15 is the IPPC standard for wood packaging in international trade, such as pallets, crates and timber dunnage.
- Stretch Wrap
Stretch wrap, or stretch film, is elastic plastic, usually LLDPE, wound under tension around a pallet load so the cartons hold together and do not shift.
Covered in these guides
Deck, Hatch Cover and Tank Top Strength: UDL, Point Loads and Load Spreading
How to read t/m² limits for decks, hatch covers and tank tops, why point loads differ from UDL, spreading loads with dunnage and steel beams, with worked examples.
5 min read Vessel stowageGeneral Cargo and Breakbulk Stowage: Holds, Stowage Factor and Discharge Order
How to plan general cargo stowage in holds and tween decks, work out stowage factor and broken stowage, check tank top loads and set a clean discharge order.
6 min read Vessel stowageDeck Cargo Barge Stowage (180–330 ft): Deck Load, CoG, Trim and Sea-Fastening
A guide to stowing 180–330 ft deck cargo barges in Indonesia, covering deck load in t/m², zones, CoG targets, trim and heel, sea-fastening, dunnage and a worked example.
6 min read Maritime professionalsCargo Lashing and Securing: CTU Code Principles, MSL and a Worked Example
How to secure cargo in containers and trucks with blocking, bracing, lashing and friction under CTU Code principles, with an acceleration table and a worked example.
6 min read Load calculationsHow Many Pallets Fit in a 20ft, 40ft and 40HC Container
Work out how many 1200 × 1000, EUR and 1100 × 1100 pallets fit in 20ft, 40ft and 40HC containers, with floor patterns, double stacking and weight limits.
5 min read Load calculationsHow Many Cartons Fit in a Container? 20ft, 40ft and 40HC Calculation
Work out how many cartons fit in a container with per-axis grid math, orientation, a payload weight check, stacking strength and mixed-SKU loads.
6 min read