c. Water Sample Collection.
(1) Water samples for identification or verification of biological agent contamination are collected by PVNTMED personnel. The supporting laboratory should provide guidance on sampling procedures and collecting kits for use in collecting the samples. In the absence of guidance, a technique for use of the Sep-PakTM is described in FM 3-19.
(2) When sampling kits are not available, samples may be collected in other available sterile containers. The best containers for use are the 100-ml glass bottles used for collecting routine water samples. All water samples must be collected and placed in a cooler or refrigerator until the sample is transported to its destination. During transportation the samples must be maintained at a temperature between 1°C and 4°C.
d. Food Samples. Veterinary personnel must collect suspect biologically contaminated food samples for submission to the supporting laboratory for in-theater verification of contamination. All food samples must be collected and placed in sterile containers. Place the samples in a cooler or refrigerator until the sample is transported to its destination. During transportation the samples must be maintained at a temperature between 1°C and 4°C.
e. Animal Specimens. Veterinary personnel collect specimens from suspect biologically contaminated/diseased animals. The same types and amounts of specimens are prepared and shipped in the same manner as are human specimens.
f. Environmental Samples. Environmental samples are collected as directed in the operators' manual or other publications for operating collection systems. Example: The Biological Integrated Detection System (BIDS) collects an environmental sample using a single liquid sample collector. The collector is a high-volume aerosol sampling and collection device. On demand it samples ambient air through a two-stage virtual impactor that concentrates aerosol particles in the 2 to 10 micrometer diameter-size range. The concentrate particle stream is directed through a wet collector containing a buffer solution and, over a 45-minute period, a 40 to 50 ml sample is collected. On order or when test results indicate a suspected agent, the sample and associated documentation are packaged and transported IAW FM 3-101-4.
B-4. Chain of Custody
a. A strict chain of custody must be maintained for every sample/specimen collected. Use DD Form 1911 (Material Courier Receipt), or other document (such as DA Form 4137 [Evidence/Property Custody Document]) as directed for each sample/specimen collected. The chain of custody document must accompany the sample/specimen during transport from the point of collection to the final receiving laboratory. Each time the sample/specimen is transferred to another individual, the receiving person must sign the document to show that they received the sample/specimen and state what happened to the sample/specimen while in their custody. The document will provide the answer to the following questions:
- When was the sample/specimen collected?
- Who has maintained custody of the sample/specimen?
- What has been done with the sample/specimen at each change of custody?
b. The samples/specimens must be appropriately packaged, labeled, and evacuated to the designated medical laboratory for confirmation of a biological attack. The standard chain of custody for the evacuation would be as follows: