The final SARC Forensic Cleaning Validation report has been published and is available to you on Knowledge Hub.

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Cleaning

Chlorhexidine wipes were also tested for cleaning instrumentation. In general, all gave acceptable performance on most substrate/body fluid combinations, provided they were cleaned with a double spray/wipe process.

Watch the SARC National Cleaning Validation Webinar to find out more details on the outcome from this phase 1 testing.

The following recommendations were made from phase 1:

Spraying or using impregnated wipes are equally effective.

Impact of different chemical concentrations; No significant improvement from using concentrations different to manufacture recommendations.

Recommend continue with using manufacture recommendations.

Impact of different chemical contact times;

Recommend ~30 seconds contact time.

Wiping sensitive instrumentation; Chlorhexidine wipes very effective

Effectiveness on different substrates; Formica most readily decontaminated, vinyl less so

Following phase 1 testing additional mechanical action and double spray assessments were made in phase 2 testing.

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Page 2 Cleaning

 

 

 

 

 

The outcomes from phase 2 testing were:

Repeated uni-directional wiping with / without multiple cloth surface changes proved to be effective but no improvement over directional circular wiping of flat surfaces.

Double spray / wipe for all test chemicals plus new Chemgene MedLab. Assessed using “acid test” of dried semen staining on vinyl.

Presept was found to be the best performing chemical in these tests with Virkon and Selgiene also demonstrating 100% DNA quantification reduction.

Since completing the validation Chemgene HLD4H was due to be discontinued and replaced with Chemgene MedLab. Phase 3 involved comparison of these 2 chemicals.

The following observations/conclusions have been made following this phase 3 testing:

Chemgene MedLab slightly less effective than HLD4H for all body fluid and surface combinations compared.

If SARCs choose to switch to Chemgene MedLab or continue using Microsol or Virusolve it is recommended they carefully monitor contamination levels on vinyl surfaces & consider additional periodic decontamination e.g. using a bleach-based cleaner where required.

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Page 3 Cleaning

 

 

 

 

 

Please do get in contact if you have any questions relating to this validation: Michelle.gaskell@dorset.pnn.police.uk

 The final Forensic Cleaning Validation report & printable version of this news article have been published and are available to you on Knowledge Hub.