Board Packaging and Shipping Requirements
A finished assembly is at its most vulnerable between the end of test and the moment the customer opens the box. Every handling step in that interval can introduce damage that no inspection will find, and the cost of the protection is trivial compared with the cost of a field failure.
Packaging is therefore a specification rather than a purchasing decision. What goes in the bag, how the boards are separated, how the carton is marked and what the customer must do on receipt are all engineering requirements that belong in the documentation.
Why Finished Boards Need Protection
A bare board is inert, while an assembled board carries components that can be cracked, joints that can be stressed and coatings that can be scratched. The packaging has to prevent mechanical shock, static discharge, moisture uptake and contamination at the same time.
The most common damage is not dramatic: a corner of a panel chipped by another panel, a component cracked by a stack that was too tall for its box, or a coating marked by a bag that was pulled across it.
Moisture Barrier Bags and Desiccant
Where the assembly carries moisture sensitive parts, the outer protection is a moisture barrier bag with a desiccant and a humidity indicator card. The bag is sealed and the card shows whether the seal held during transport.
The bag size should match the stack rather than the carton, because a bag that is much larger than its contents is difficult to seal flat and is easily punctured. The seal width and the seal quality are part of the specification.
Separators, Trays and Edge Protection
Boards should be separated by a material that does not abrade the surface, and the separation should prevent any relative movement. Foam, moulded trays and edge protectors all achieve this, and the choice depends on the quantity and the shape.
Edge protection is the detail that prevents most transit damage, because the corners of a panel are the parts that strike the box. A moulded tray that supports the board by its edges distributes the load away from the components.
Static Protection
All packaging that touches an assembly should be dissipative rather than insulative or fully conductive. A dissipative bag drains charge slowly, which is what protects a device from a fast discharge when the bag is opened.
The rule extends to the inner packaging, since a board that is protected outside and then poured onto a plastic tray inside has lost the protection. The static requirement is the same one that governs handling practice.
Stacking and Mechanical Load
The carton has to survive the stacking load that the shipper will apply, and the boards inside have to survive the carton. A box specification that is adequate for a paper product is usually not adequate for a metal panel.
The test is a drop and a vibration test on a packed carton, which is a standard service and is worth running once for a new package rather than after a complaint. The result also feeds the design of the inner tray.
Labelling and Identification
Every carton should identify the product, the quantity, the revision, the build date and the handling requirements. The label should also carry the moisture sensitivity level where it applies, so the receiving inspection knows what to check.
The labelling should be readable without opening the carton, because opening it to identify the contents defeats the moisture protection. This is the same traceability principle that applies on the board itself, in the practice described for labelling and traceability.
Shipping Conditions
Temperature and humidity during transit can exceed the assumptions made in the factory, particularly for air freight and for containers that sit on a dock. Where the product is sensitive, the packaging has to include the protection or the timeline has to be limited.
A shipment that is expected to sit for weeks should be packed for the duration rather than for the journey, and the customer should be told the floor life that remains on arrival.
Receiving and Unpacking Requirements
The specification should state what the customer does on receipt: inspect the indicator card, record the seal condition and start the floor life clock. Without that instruction, a board that has been exposed in transit is treated as fresh.
Where a bag is found compromised, the response is a bake rather than a rejection, provided the schedule is known. That decision is described in the practice for moisture bake and it depends on the packaging record.
Verification of the Package
The package should be verified with a trial shipment and an inspection on arrival, comparing the condition of the boards with the record from the end of the line. The first shipment of a new product is the cheapest place to find a packaging problem.
Where damage is found, the carton, the tray and the separation should be examined in that order, because the failure usually starts with the outermost item.
Documentation
The packaging specification should list the bag, the desiccant, the indicator card, the tray, the carton and the label content, with the material and the size of each. It should also state the quantity per pack and the marking requirements.
The document belongs with the assembly data rather than in the logistics folder, because the receiving inspection reads it and the customer’s quality team audits it.
Additional Considerations for This Build
Practical attention to board packaging pays for itself here, because it decides whether the finished board behaves as the drawing intended. Where the requirement is not stated on the fabrication drawing or in the assembly notes, the shop has to assume a default, and that default is rarely the value the design was simulated with. Stating board packaging explicitly, together with the tolerance that applies, removes the assumption and keeps the result predictable from batch to batch.
Process Control and Verification
On a design of this kind, dissipative is the item that decides how the rest of the board is arranged. Where the requirement is not written down, the shop supplies its own default, and the default is chosen for the process rather than for the design. The measurements that matter are the repeatable ones: conductor width and spacing, annular ring, finished hole size, plating thickness and surface finish are all verifiable on a coupon that travels with the panel.
Running a first article through the same checks as the production panel confirms that the two agree, and that comparison is the cheapest form of process control available at prototype stage. Keeping a sample from the panel turns a dispute into a measurement, because the same coupon can be re-examined by both parties without rebuilding the batch.
Related reading: our fabrication notes, board quality and design release notes cover the same ground.
A first article check confirms that the process and the drawing agree on the points listed above, and that the coupon data supports the values used in the design.
Where a measurement falls outside the expected window, the sample is retained so that the cause can be established before the balance of the batch is released.
A first article check confirms that the process and the drawing agree on the points listed above, and that the coupon data supports the values used in the design.
Where a measurement falls outside the expected window, the sample is retained so that the cause can be established before the balance of the batch is released.
FAQ
Does every assembly need a moisture barrier bag? Only where a moisture sensitive part or a bare laminate requirement applies, and the class of the most sensitive part sets the answer.
Is bubble wrap acceptable? It protects against impact and provides no static protection, so it is used inside a dissipative bag rather than on its own.
How is a package validated? With a drop and vibration test on a packed carton and an arrival inspection after a real shipment.
What happens if the indicator card shows exposure? The boards are baked on the appropriate schedule before assembly rather than rejected.
