When collecting liquid samples from a fire scene, which tool should NOT be used?

When collecting liquid samples from a fire scene, a plastic cup should not be used due to the potential for contamination and chemical interaction. Plastic can absorb certain chemicals that may be present in the liquid, which could compromise the integrity of the evidence. Furthermore, plastic containers might leach chemicals into the sample, altering its composition and making it difficult to analyze accurately later on.

In contrast, tools such as a clean, sterile eyedropper, syringe, or pipette are designed to minimize contamination and preserve the chemical makeup of the liquids being collected. These tools are typically made from materials that do not react with chemical substances and allow for precise collection without introducing extraneous materials. This care in preserving evidence is crucial for forensic analysis and ensuring that the findings are reliable in any subsequent investigations or court proceedings.