Non-destructive examination
Definition
Any examination that does not consume or significantly alter the stain: visual inspection, alternate light source (ALS) examination, photography, and microscopy of an intact surface. These are always performed before any chemical test.
Related terms
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- Destructive testing
- Any test that consumes, extracts, or chemically alters the stain material: cutting a fabric swatch, swabbing a surface, adding a chemical reagent....
- Differential extraction
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- PCR inhibitor
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- Sequential testing protocol
- The standardised order in which biological stains are examined: presumptive test, then confirmatory test, then species confirmation, then typing and DNA analysis....
Explained in
- Order of Testing and DNA PreservationAny examination that does not consume or significantly alter the stain: visual inspection, alternate light source (ALS) examination, photography, and microscop...