Shipping Magnets by Air
For air shipment purposes, magnets are considered “dangerous goods” and the International Air Transport Association’s (IATA) Dangerous Goods Regulations (DGR) must be followed. According to IATA (International Air Transport Association) Packing Guideline 953 (formerly 902), a shipment with magnets falls under one of three categories:
1. Air-freight forbidden (magnetic field too large)
If the package with the magnets (including magnetic shielding packaging) creates a magnetic field of more than 0,00525 gauss (=5,25 mG = 0,525 µT) at a distance of 4,6 metres (in any direction), the transport of the package via air freight is generally forbidden.
2. Shipment unproblematic (magnetic field very small)
The second and more strict test requires that at a distance of 2,1 metres from the package a magnetic field of less than 0,002 gauss (2 mG = 0,2 µT) is created.
If the package passes this test, the content is considered “not magnetised” for transport purposes and the package can be shipped. In that case it is recommended to attach a shipping declaration that confirms that the package passed the stricter test and therefore can be viewed as non-magnetic. This can avoid possible delays due to inspections by authorities.
3. Shipment as a declared dangerous good (for all other cases)
If the package falls between the two categories, meaning the first test was passed but not the stricter second one, the package has to be declared a dangerous good, which will lead to higher shipping costs and additional work. Also, there are certain airports that cannot be used in this case.
The aim is, therefore, to pass the stricter second test and airfreight the package without special measures.
The big problem with this packing regulation lies in the fact that this measurement can only be done with expensive special equipment. Most magnetic field measuring devices cannot measure such weak magnetic fields.
A correct classification requires accurate measurements, which supermagnete cannot provide. When in doubt, we recommend to stay away from airfreight.
If the shipment is not airfreight (train, truck, ship, etc.), magnets are not considered dangerous goods.
Neodymium pot magnets
Neodymium pot magnets create a far-reaching and strong magnetic field. The mandatory tests have to be carried out accurately to avoid endangerment and monetary fines from the aeronautical authority.
Ferrite pot magnets
Ferrite pot magnets create a much weaker magnetic field than neodymium magnets. Therefore, it takes less effort to pass the mandatory tests.
In order for magnets to be shipped by air
Flux measurements of all packages containing magnets must measure less than 0.00525 gauss 15 feet from the package. (If flux measurements are less than 0.002 gauss measured 7 feet from the package, the package is not considered to contain magnetic material, and hence is not classified as a Dangerous Good. However, unless the packaging is extremely secure and there is no chance that the contents will shift or shielding will be damaged in transit, it is safer to proceed as though the package comes under the DGR.)
Packages containing magnetic materials must be clearly identified according to Packing Instructions 902. This calls for a “Magnetized Material” label to be affixed, and for a Shipper’s Declaration of Dangerous Goods to be provided to the carrier.
Personnel responsible for shipping magnets by air are required by the Federal Aviation Authority (FAA) to be trained for that purpose and for those training records to be maintained.
Contact your carrier for more information and guidelines.
Note that in addition to transportation costs, Dangerous Goods fees apply to each package shipped by air, making shipping magnets by air quite costly.
Packaging magnetic materials for air shipment must be accomplished considering the above. Powerful magnetic components and assemblies need to be shielded so that magnetic fields will meet air shipment criteria. Packaging may need to be designed using Finite Element Analysis methods.
Thus re-packaging or re-arranging packaging certified for air shipments will void the original certification.
An example of how magnetic fields can be contained is illustrated in the FEA models.