Wet Evidence Drying
Definition
The mandatory air-drying step for any wet biological sample before sealing. Sealing wet evidence traps moisture, promotes bacterial growth, and degrades DNA. Most protocols require a minimum 30-60 minutes air-dry before the envelope is sealed.
- Requirement
- Air-dry before sealing any wet biological sample
- Minimum time
- Commonly 30 to 60 minutes
- Risk if skipped
- Bacterial growth and DNA degradation
- Applies to
- SAFE kit swabs and other biological exhibits
Common questions
Why can't a wet swab simply be sealed immediately after collection to save time?+
Trapped moisture inside a sealed container promotes bacterial growth almost immediately, and the resulting degradation can destroy the DNA profile before the sample ever reaches the laboratory.
Where should wet evidence be dried before packaging?+
It is air-dried in a designated drying area away from direct sunlight, other biological samples, and contamination sources, using a drying rack or stand rather than laying items flat on an uncontrolled surface.
Related terms
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- Kit Shelf Life
- The period during which an unused sealed SAFE kit remains usable, typically 2-5 years depending on the manufacturer and storage conditions. Expired...
- Reference Sample
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- SAFE Kit
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