Paper bags work well for both fresh and dried blood or semen stains , for example. Paper evidence collection bags are also useful for storing fabric and textile evidence because air permeability is beneficial with this type of evidence.
Why is evidence placed in a paper bag?
Each item is placed in a separate paper bag to prevent cross-contamination . Plastic bags are not used because moisture can collect within the bag and alter the evidence (Figure 3). Do not remove attached hairs or fibers from clothing.
What evidence is packaged in paper bags?
Evidence that is wet or that may contain body fluids (blood, semen, etc.) must be air-dried completely . Such items should be packaged in paper bags/boxes. Known samples can be collected by rubbing sterile swabs against the cheek, inside the mouth.
What is the main advantage of using paper bags?
Pros of Using Paper Bags
Paper bags are 100% biodegradable, reusable, and recyclable . Many paper bags can withstand more pressure or weight than plastic bags. Paper bags present less of a suffocation risk to young children or animals.
What are brown paper evidence bags used for?
Paper bags work well for both fresh and dried blood or semen stains , for example. Paper evidence collection bags are also useful for storing fabric and textile evidence because air permeability is beneficial with this type of evidence.
What can degrade a biological sample collected as evidence?
Improperly used, bleach could destroy biological evidence. There will be occasions when it is not possible to collect a stain by cutting it from an object (e.g. stain is on a concrete floor). ... It may be useful to test the “unstained” area with an appropriate presumptive test to see if it contains a biological sample.
Which type of evidence should never be packaged in plastic containers?
There's a simple rule of thumb for deciding which type of evidence packaging—wet evidence goes in paper containers (wet evidence can degrade if placed inside plastic containers) and dry evidence goes in plastic. Items that could be cross-contaminated must be packaged separately.
Can biological evidence be put in a plastic bag?
When transporting and storing evidence that may contain DNA, it is important to keep the evidence dry and at room temperature. ... Never place evidence that may contain DNA in plastic bags because plastic bags will retain damaging moisture .
What do investigators do with wet items?
Moist or wet evidence (blood, plants, etc.) from a crime scene can be collected in plastic containers at the scene and transported back to an evidence receiving area if the storage time in plastic is two hours or less and this is done to prevent contamination of other evidence .
What are some disadvantages of cloth bags?
The two disadvantages of cloth bags are that you have to pay for them and sometimes people forget their bags at home . Overall, the best bag to use would be the cloth bag. Cloth bags can be reused about 500 times. If people use cloth bags then less oil and trees will be used to make plastic and paper bags.
What are the advantages and disadvantages of using paper bags?
Advantages and disadvantages of using paper bags
Paper bags are 100% biodegradable, reusable and recyclable . Many paper bags can bear more pressure or weight than plastic bags. Paper bags are less likely to choke on young children or animals. Unlike their plastic counterparts, paper bags are not waterproof.
Are paper bags really better for the environment?
Paper bags have some advantages over plastic bags when it comes to sustainability. They are easier to recycle, and, because they are biodegradable , they can be used for purposes like composting.
What are the 5 steps of crime scene investigation?
The basic crime scene procedures are physical evidence recognition, documentation, proper collection, packaging, preser- vation, and, finally, scene reconstruction .
How can blood spatter evidence be used long after the crime?
Blood evidence can also point the investigator in the direction he or she needs to go to solve the case. If blood evidence is documented, collected, and stored suitably, it can be presented to a judge or jury several years from the time of the criminal act .
What is the correct method of packaging evidence?
Evidence submitted must be in sealed containers whenever possible. Evidence tape is the preferred sealing method. Seals must be marked with initials of the officer and the date sealed. Any evidence for which Forensic Biology/DNA analysis may be requested must be handled with clean techniques.
What type of evidence should be collected first?
In order of collection, the most fragile evidence must be collected first . A crime scene investigator may start with hairs and fibers and fingerprints and then work his or her way through the evidence, peeling back one layer at a time.
