Export Packaging Guide: Materials, Standards, and Moisture & Corrosion Protection

Export packaging protects goods through some of the harshest conditions in any supply chain: weeks in a shipping container, temperature swings between climate zones, salt air off ocean freight lanes, rough port handling, and customs inspections in countries with their own compliance requirements. For manufacturers, defense contractors, and industrial exporters, the cost of inadequate export packaging is not just a damaged shipment; it is delayed programs, failed inspections, and replacement costs that dwarf the original packaging budget.

This guide covers the materials, standards, and protection methods that matter most for getting goods to their destination intact.

What Is Export Packaging and Why It Matters

Export packaging encompasses the full system of materials, structures, and protective components used to prepare goods for international transit. It is distinct from domestic packaging in two important ways: the duration and severity of exposure are significantly greater, and the compliance requirements span multiple regulatory frameworks across origin and destination countries.

The cost of packaging failure in export logistics is well documented. Goods damaged in transit generate claims, replacement shipments, import duty complications, and program delays. For defense and aerospace exporters, a packaging failure on a critical component can have mission-level consequences. Investing in the right export packaging standards from the outset is consistently less expensive than addressing failures after the fact.

For a broader overview of how protective packaging reduces losses, see our guide on minimizing losses with protective packaging.

Key Risks During International Transit

Understanding the specific hazards of international shipping is the starting point for selecting the right export packaging system. The most damaging risks for most exported goods are:

• Container condensation (container rain): Temperature swings as a vessel moves between climate zones cause moisture in the container air to condense on cooler surfaces, including the goods themselves. This is one of the leading causes of corrosion, mold, and moisture damage in ocean freight, and it cannot be solved by waterproof outer packaging alone.
• Salt air and humidity: Ocean freight environments expose goods to elevated salt air and humidity levels throughout transit, accelerating corrosion on bare metal surfaces and degrading moisture-sensitive components.
• Temperature extremes: Goods passing through tropical ports or stored in unventilated containers can experience temperatures well above standard ambient conditions. Goods transiting northern routes in winter face the reverse. Both extremes can affect adhesives, electronic components, and materials with narrow operating ranges.
• Extended dwell time: Ocean freight shipments regularly spend weeks in transit, with additional time at port, in customs, or in destination warehousing. Packaging must maintain its protection function not just during active transit but through the full storage period.
• Rough handling: Port equipment, cargo transfer, and last-mile delivery all introduce impact and vibration loads that can damage inadequately cushioned or structurally insufficient packaging.

Types of Export Packaging Materials

• Effective export packaging is a system of complementary materials, each addressing a different risk. The table below maps the most common export packaging materials to the hazards they address and the applications they serve best.

Shipping overseas? Royco stocks MIL-SPEC barrier bags, VCI corrosion protection, and desiccants that protect against moisture and corrosion in transit.

Shop Export Packaging

Moisture and Corrosion Control for Export Shipments

Moisture and corrosion are the primary causes of export packaging failure for industrial, defense, and aerospace goods. Corrugated cartons and wood crates address physical impact but provide no meaningful barrier against water vapor or salt air. Protecting moisture-sensitive and corrosion-susceptible goods in ocean freight requires a dedicated inner packaging system built around three components:

Barrier Bags (MIL-PRF-131)

MIL-PRF-131 barrier bags are foil-laminate heat-sealable bags that achieve near-zero moisture vapor transmission rates (MVTR approaching 0.002 g/m2/24h). When heat sealed around a component with a desiccant pack inside, a MIL-PRF-131 bag creates a controlled dry microenvironment that remains stable for months or years regardless of the external humidity conditions in the shipping container.

For defense export applications, MIL-PRF-131 barrier bags are a standard element of Method 50 barrier protection under MIL-STD-2073.

VCI (Vapor Corrosion Inhibitor) Packaging

VCI packaging emits corrosion-inhibiting molecules that form a protective molecular layer on exposed metal surfaces. For bare metal parts such as machined components, fasteners, gears, and structural assemblies, VCI bags, papers, and emitters provide active corrosion protection that passive barrier materials alone cannot deliver. VCI is particularly valuable for ocean freight applications where salt air and humidity are unavoidable.

See our guide to corrosion protection for export packaging for a step-by-step overview.

Desiccant Packs (MIL-D-3464)

Desiccant packs placed inside a sealed barrier bag adsorb residual moisture in the enclosed air space, maintaining low internal humidity throughout the transit and storage period. For long-duration ocean freight shipments, silica gel, clay, or molecular sieve desiccants are specified based on the volume of enclosed air and the expected duration of protection. Humidity indicator cards placed alongside the desiccant provide a visual confirmation at the point of opening whether the sealed environment remained within acceptable limits.

Royco's MIL-D-3464 desiccant packs range from 1/6 unit to 80 units to cover any container volume.

Used together, barrier bags, VCI materials, and desiccants form a complete moisture and corrosion protection system suited to the demands of international ocean and air freight.

Export Packaging Standards and Compliance

Several standards and specifications govern export packaging requirements depending on the goods, destination, and customer:

• ISPM 15 (International Standards for Phytosanitary Measures No. 15): ISPM 15 packaging requirements apply to any wood packaging material, including crates, pallets, and dunnage, used in international shipments. The standard requires heat treatment or methyl bromide fumigation of the wood to prevent the spread of pests and diseases across borders, followed by the IPPC stamp confirming compliance. Most major trading countries, including the United States, the European Union, China, and Australia, enforce ISPM 15 at import. Non-compliant wood packaging can result in shipment refusal, fumigation at destination costs, or destruction of goods.
• ISO and ISTA testing standards: The International Organization for Standardization (ISO) and International Safe Transit Association (ISTA) publish test protocols that simulate the physical conditions of international shipment: vibration, drop, compression, and climate. Testing to these protocols before export provides documented evidence that the packaging design can withstand the expected transit conditions and is a requirement for some industrial and government customers.
• MIL-STD-2073 for defense export packaging: For defense and government contracts, MIL-STD-2073 is the governing military packaging standard. It defines preservation methods (including Method 50 barrier protection), packaging levels, marking requirements, and the materials that must be used at each level. Defense exporters must comply with MIL-STD-2073 requirements as called out in their contracts, which typically means barrier bags, desiccants, and humidity indicators as a minimum for sensitive components.
• IMO and IATA regulations: International Maritime Organization (IMO) and International Air Transport Association (IATA) regulations govern the packaging, labeling, and documentation of hazardous materials in ocean and air freight. Exporters shipping any classified hazardous goods must comply with IMDG Code (ocean) or IATA DGR (air) requirements, which include specific packaging performance standards and marking requirements.
• Customs and import requirements: Each destination country maintains its own import packaging and labeling requirements. Researching and adhering to the regulations of the destination country before shipment avoids delays, penalties, and the risk of goods being held or destroyed at customs.

Best Practices for Export Packaging

With materials selected and compliance requirements identified, the following practices apply to any international shipping packaging program:

• Size packaging correctly: Leave adequate clearance between the product and the inner walls of the carton or crate for cushioning material. Do not leave large voids, which allow goods to shift; fill empty space with appropriate void-fill.
• Seal barrier bags before closing outer packaging: Heat seal barrier bags with desiccants and humidity indicators inside before placing in cartons or crates. The barrier bag is the innermost and most critical layer of protection.
• Label clearly and completely: Mark packages with product details, handling instructions (fragile, this side up, keep dry), destination address, origin country, and any required regulatory markings including ISPM 15 stamps on wood packaging. Incomplete labeling is a leading cause of customs delays.
• Maintain documentation: Ensure all customs forms, commercial invoices, packing lists, certificates of conformance, and shipping manifests are accurate, consistent with each other, and accompany the shipment. For defense exports, end-use certificates and export license documentation must be in order before goods leave the facility.
• Test before shipping: Where volume or value justifies it, test the complete packaging system against the relevant ISTA or ISO protocol before the first production shipment. This identifies design weaknesses before they result in damage claims.

How to Choose the Right Export Packaging

Use the following decision framework to select the appropriate export packaging system for your shipment:

• High-value or precision components (electronics, aerospace parts, military equipment): Specify barrier bag protection (MIL-PRF-131 or MIL-PRF-81705 for ESD-sensitive items), desiccants, and humidity indicators as a minimum. Add VCI materials for any bare metal surfaces. Outer packaging should be a rigid crate or reinforced corrugated carton with adequate cushioning.
• Bare metal parts or assemblies susceptible to corrosion: VCI bags, papers, or emitters are essential. Combine with a sealed barrier bag and desiccants for ocean freight applications where salt air and container condensation are unavoidable.
• Heavy industrial equipment or machinery: Wood crates with ISPM 15 compliant treatment for most international destinations. Inner components should still be barrier-bagged and desiccated if they are moisture-sensitive. Ensure wood is properly stamped before export.
• General non-sensitive goods for air freight: Corrugated cartons meeting destination country and carrier requirements, with appropriate inner cushioning. Transit time is shorter, reducing moisture exposure risk, but impact and handling hazards remain.
• Defense and government contract shipments: Review the contract for MIL-STD-2073 requirements and apply the specified method (typically Method 50 for sensitive components) using qualified packaging materials. Certificates of conformance from the packaging supplier are typically required.

Get Export Packaging from a Qualified Supplier

Royco Packaging has supplied defense contractors, aerospace manufacturers, and industrial exporters with export packaging materials for more than 40 years. We stock MIL-PRF-131 barrier bags, MIL-D-3464 desiccants, VCI corrosion protection, and MIL-STD-2073 compliant packaging materials in-house for same-day shipment. Custom sizes and configurations are available, and all MIL-SPEC orders include certificates of conformance. Royco holds ISO 9001:2015 certification.

Need help specifying export packaging for defense or industrial shipments? Call 1-800-67-ROYCO or email sales@roycopackaging.com.