When handling blood samples, what is a necessary safety procedure Mary should follow?

Using a shield when opening containers is critical for ensuring safety in a laboratory setting, especially when handling blood samples. This procedure minimizes the risk of exposure to splashes or aerosolization of potentially infectious materials. Blood samples can contain pathogens, and unprotected handling can pose a significant risk to the laboratory personnel.

The implementation of a shield provides a barrier that protects both the individual and the surrounding environment from any hazardous spills or aerosol that may escape during the process of opening containers. This is especially important in preventing contamination and ensuring a safe working environment.

In contrast, covering the sample with a cloth may not offer adequate protection against spills or exposure, while wearing double gloves could provide an extra layer of protection but does not directly address airborne or splash risks. Minimizing movement in the lab, while contributing to safety, does not specifically mitigate the immediate hazards associated with handling blood samples. Therefore, using a shield when opening containers stands out as the most effective and targeted safety procedure in this context.