"In response to well documented quality problems in labs that were previously considered reliable, the federal government established certification programs. The U.S. Department of Health and Human Services has a program to certify laboratories.3 And the U.S. Department of Transportation has a program.4 Testing conducted by federal agencies or required by federal law must be conducted by certified labs."

Source

Maltby, Lewis, "Latest Research Reveals New Problems with Drug Testing," National Workrights Institute (Princeton, NJ: March 2012), p. 1.
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