What should technicians do if they encounter unknown substances at a crime scene?

When technicians encounter unknown substances at a crime scene, it is crucial to avoid any contact and report the situation to the appropriate authorities. This approach ensures the safety of the technician and maintains the integrity of the scene. Unknown substances could potentially be hazardous or carry biological, chemical, or toxic properties that pose risks. By refraining from interaction with the substance, technicians prevent accidental exposure or contamination.

Reporting the substance to authorities allows trained professionals to handle the situation, which may include conducting specific tests to identify the substance safely. This procedure is not only a matter of personal safety but also aligns with proper protocols for evidence handling at crime scenes. It helps maintain the evidential chain, ensuring that any analysis or investigation can proceed without interference from untrained personnel.

Engaging directly with unknown substances could lead to unintended consequences, such as contamination or harmful exposure, undermining the investigation's efficiency and outcomes. Hence, avoiding contact and escalating the issue to authorities is the best course of action in such scenarios.