Clean (ideally sterile) syringes or disposable pipettes should be used to collect liquid blood, which should then be transferred to a clean (preferably sterile) test tube. With a clean spatula, a blood clot may be moved to a clean test tube. To absorb liquid blood or a blood clot, a clean cotton towel can be used (avoiding areas containing only serum).
If wet blood samples are taken, they must be preserved in an anticoagulant and stored in a refrigerator. These samples should be sent to the lab as soon as possible. Label the specimens with the case number, item number, date, time, location, and the name of the evidence collector.
Also Read: Blood Spatter Analysis
■ Wet Bloodstains: Small objects with wet bloodstains should be left to air dry before being collected. An attempt should be made to keep any bloodstain patterns intact during packaging and transit. Wet bloodstains may be seen on large objects that cannot be removed from a crime scene. Wet blood should be wiped using a clean cotton cloth. Allow bloodstained cotton fabric to air dry before placing it in a paper container. Each object and container must be labelled correctly.
■ Dried Bloodstains: on removable items Dried bloodstains on weapons, clothing, and other mobile objects should be gathered separately rather than as a whole. Each item should be placed in its own (paper) container, which should be securely sealed and labelled. The bloodstain pattern should be noted and drawn as needed. The stain can be removed off the object using tape or scraped off with a clean piece of paper. The tape lifter or the blood crusted paper can then be placed in a “druggist fold” and sealed in an envelope. Each item must be appropriately labelled.