Decontamination of Samples Decontamination of Samples and Evidenceand Evidence

Sample and Evidence CollectionSample and Evidence Collection

• All samples and evidence are collected All samples and evidence are collected following best work practices for sampling following best work practices for sampling and forensic collection proceduresand forensic collection procedures

• All samples are placed in a plastic bag All samples are placed in a plastic bag after collection and required after collection and required documentation is completeddocumentation is completed

Sample and Evidence Sample and Evidence Decontamination: Chem-Bio Decontamination: Chem-Bio

• Samples and evidence require their own Samples and evidence require their own decontamination stationsdecontamination stations

• Stations are usually found in the Exclusion Stations are usually found in the Exclusion Zone near the equipment drop stationZone near the equipment drop station

Station 1: Applying Decon SolutionStation 1: Applying Decon Solution

Plastic bag is washed with an appropriate Plastic bag is washed with an appropriate decontamination solution (i.e. bleach solution decontamination solution (i.e. bleach solution 5%, DS-2, Sandia Foam, etc..)5%, DS-2, Sandia Foam, etc..)

Station 2:Contact TimeStation 2:Contact Time

• Most decontamination solutions require 15-30 Most decontamination solutions require 15-30 minutes contact timeminutes contact time

• Contact time : is the amount of time that the Contact time : is the amount of time that the decontamination solution is in contacted with the decontamination solution is in contacted with the suspected agentsuspected agent

• Decon solution must remain “fresh” on the Decon solution must remain “fresh” on the sample or evidence (may require multiple sample or evidence (may require multiple sprayings, soakings, floatings)sprayings, soakings, floatings)

Contact EvaluationContact Evaluation

• A test was conducted to verify that data A test was conducted to verify that data could be recovered from a photo CD using could be recovered from a photo CD using standard Decon solutions.standard Decon solutions.

• CD were submerged into the Decon CD were submerged into the Decon solution for the duration of the contact timesolution for the duration of the contact time

Photo CD Test ResultsPhoto CD Test Results

Decon SolutionDecon Solution Contact timeContact time Retrievable InfoRetrievable Info

AmmoniaAmmonia 15/3015/30 YesYes

AcetoneAcetone 1515 NoNo

5% HTH (Chem)5% HTH (Chem) 15/3015/30 YesYes

2% HTH (bio)2% HTH (bio) 15/3015/30 YesYes

10% Sodium 10% Sodium BicarbonateBicarbonate

15/3015/30 YesYes

5% Bleach (Chem)5% Bleach (Chem) 15/3015/30 YesYes

2/10 parts Bleach (bio)2/10 parts Bleach (bio) 15/3015/30 YesYes

10% Sodium 10% Sodium Hydroxide+10% Hydroxide+10% AlcoholAlcohol

1515 NoNo

Station 2: Technical IssuesStation 2: Technical Issues

• Air timeAir time

• Chain of CustodyChain of Custody

Station 3: RinseStation 3: Rinse

The sample/evidence bag is rinsed with The sample/evidence bag is rinsed with de-ionized waterde-ionized water

The objective is not to introduce any The objective is not to introduce any outside contaminates that may be found in outside contaminates that may be found in tap water and other bottled water.tap water and other bottled water.

Rule of thumb: use the purest availableRule of thumb: use the purest available

Station 4:DryingStation 4:Drying

• All sample/evidence bags are dried using All sample/evidence bags are dried using disposable rags, absorbent pads, air disposable rags, absorbent pads, air drying, etc..drying, etc..

• The waste is collected and held for proper The waste is collected and held for proper disposal disposal

Station 5: Double BagStation 5: Double Bag

• The sample/evidence bag is then place inside a The sample/evidence bag is then place inside a second plastic bag that is being held in the second plastic bag that is being held in the decontamination reduction corridor .decontamination reduction corridor .

• Sample/evidence bag is then passed down the Sample/evidence bag is then passed down the Decon line to the contamination control lineDecon line to the contamination control line

• Sample/evidence bag is then placed in a third Sample/evidence bag is then placed in a third bag inside the support zone and is turned over bag inside the support zone and is turned over to the sample/evidence custodianto the sample/evidence custodian

Station 5: Technical IssuesStation 5: Technical Issues

• Decon team members touching the Decon team members touching the sample/evidence bag are clean having just sample/evidence bag are clean having just entered the Decon lineentered the Decon line

• Sample/evidence bag is in line of sight of Sample/evidence bag is in line of sight of the sample/evidence custodian at all timesthe sample/evidence custodian at all times

Decontamination: RADDecontamination: RAD

• Radiological Surface Contamination Radiological Surface Contamination

Station 1: Removal of Surface Station 1: Removal of Surface ContaminationContamination

Standard military medical practices spray the Standard military medical practices spray the items with standard Decon solutions which will items with standard Decon solutions which will remove any contaminantsremove any contaminants

Plastic bag is carefully wiped or vacuumed Plastic bag is carefully wiped or vacuumed

Remember you are dealing with particulate Remember you are dealing with particulate matter and want to limit the spread of matter and want to limit the spread of contaminationcontamination

Station 2: RinseStation 2: Rinse

The sample/evidence bag is rinsed with The sample/evidence bag is rinsed with de-ionized waterde-ionized water

The objective is not to introduce any The objective is not to introduce any outside contaminates that may be found in outside contaminates that may be found in tap water and other bottled water.tap water and other bottled water.

Rule of thumb: use the purest availableRule of thumb: use the purest available

Station 3 :DryingStation 3 :Drying

If possible a surface wipe should be collected If possible a surface wipe should be collected and tested for residual surface contaminationand tested for residual surface contamination

Station 4: Double BagStation 4: Double Bag

• The sample/evidence bag is then place The sample/evidence bag is then place inside a second plastic bag that is being inside a second plastic bag that is being held in the decontamination reduction held in the decontamination reduction corridor .corridor .

• Sample/evidence bag is then passed Sample/evidence bag is then passed down the Decon line to the contamination down the Decon line to the contamination control linecontrol line

Draft MethodDraft Method

Dealing with samples at the Decon line:

• Step 1: At the start of the Decon line Place the double-bagged sample into the plastic container provided at the designated Sample Decon Station.

Draft MethodDraft Method

• Step 2: Using the Decon equipment provided at the Sample Decon Station, begin by decontaminating the outer gloves. Mist the gloves with the Decon solution. Scrub the gloves with the brush provided. Finish Decon by misting the gloves with the rinse solution.

Draft MethodDraft Method

• Step 3: Decontaminate the outer Ziploc baggie utilizing the same procedure preformed for the outer gloves.

Draft MethodDraft Method

• Step 4: Completely dry the outside of the sample baggie and gloves with the disposable wipes provided at the Sample Decon Station. Dispose of the wipes in the container provided at the Sample Decon Station.

Draft MethodDraft Method

• Step 5: Place the decontaminated sample baggie in another Ziploc bag, label the bag, then transfer the sample to the container located at the “clean” side of the Sample Decon Station.

Draft MethodDraft Method

• Step 6: M-8 paper and monitoring equipment can be used to verify that proper Decon has been performed.

Technical IssuesTechnical Issues

Currently this draft procedure does not Currently this draft procedure does not consider evidence and chain of custody or consider evidence and chain of custody or documentation of samplesdocumentation of samples