If relying on a courier, mail, or contract delivery system to send your samples to the laboratory, ensure your packaging is sturdy and padded to avoid accidental breakage of cassettes and air sampling tubes.
Use of cardboard boxes and/or coolers and bubble wrap or styrofoam peanuts will save you the extra work of recollecting samples should a sample break in shipment.
Also, when shipping using these services, it is advantageous to have the courier, shipping center sign the chain of custody prior to closing the box. These individuals can also assist in packaging the samples to ensure they do not break.
The analytical method will identify when samples need to remain cool in transit or otherwise manipulated prior to sending them to the laboratory. The laboratory can also be a resource to ensure proper shipment and prepartion of the samples. When in doubt, call the laboratory and let them know what you are sending requesting information on any special considerations for shipment.