How to Collect Dried Blood from a Crime Scene
Collecting dried blood from a crime scene is a crucial task for forensic investigators. Bloodstains can provide valuable evidence about the nature of the incident, the victims, and the perpetrators. This article will guide you through the proper procedures for collecting dried blood from a crime scene to ensure accurate and reliable evidence.
Preparation
Before collecting dried blood, it is essential to prepare yourself and the necessary equipment. Here are some key steps to follow:
1. Personal Protective Equipment (PPE): Wear appropriate PPE, including gloves, a mask, and a lab coat to prevent contamination and protect yourself from potential hazards.
2. Documentation: Take detailed notes of the crime scene, including the location of the dried bloodstains, the surrounding environment, and any other relevant information.
3. Equipment: Gather the necessary equipment, such as swabs, forceps, evidence bags, and a clean, sterile container for transporting the collected samples.
Identification and Documentation
The first step in collecting dried blood is to identify and document the bloodstains. Here’s how to do it:
1. Photograph the bloodstains: Use a camera to document the bloodstains’ location, size, shape, and any other distinctive features.
2. Measure the bloodstains: Use a ruler or measuring tape to determine the size of the bloodstains, which can help in determining the amount of blood involved.
3. Document the surrounding area: Note any relevant details about the area surrounding the bloodstains, such as carpet fibers, fabric, or other potential evidence.
Collection Techniques
Once you have identified and documented the bloodstains, it’s time to collect the dried blood. Here are some techniques to consider:
1. Swabbing: Use a sterile swab to gently collect dried blood from surfaces. Apply gentle pressure to avoid disturbing the stain or causing further contamination.
2. Scraping: If the bloodstain is on a hard surface, use a sterile scalpel blade or forceps to carefully scrape the dried blood into a sterile container.
3. Lift: For bloodstains on soft surfaces, such as fabric or carpet, use a sterile forceps to lift the dried blood and place it into a sterile container.
Transportation and Storage
After collecting the dried blood, it is crucial to transport and store the evidence properly to maintain its integrity. Here are some guidelines:
1. Use evidence bags: Place the collected dried blood into a clean, sterile evidence bag, ensuring that it is sealed tightly to prevent contamination.
2. Label the evidence: Clearly label the evidence bag with the date, time, location, and a brief description of the contents.
3. Store the evidence: Store the evidence bag in a cool, dry place, away from direct sunlight and extreme temperatures.
By following these steps, forensic investigators can collect dried blood from a crime scene effectively and ensure that the evidence is preserved for further analysis. Proper collection and handling of evidence are essential for building a strong case and bringing justice to the victims.
