Compare BSL-2 and BSL-3 containment features and give a typical example of work at each level.

Compare BSL-2 and BSL-3 containment features and give a typical example of work at each level.

• A. BSL-2: standard practices, limited access, biological safety cabinet, PPE; example: Staphylococcus aureus. BSL-3: negative-pressure rooms, directional airflow, sealed penetrations, respirators; example: Mycobacterium tuberculosis.
• B. BSL-2 uses negative pressure; BSL-3 does not; example: reversed.
• C. BSL-2 uses no PPE; BSL-3 uses minimal PPE.
• D. BSL-2 is used in office settings; BSL-3 in clinical labs.

Answer: (A)

Containment levels rise with the degree of engineering controls and protective gear used. At the BSL-2 level, the focus is on standard lab safety with restrictions on access, routine biosafety practices, and the use of a biological safety cabinet for procedures that could generate splashes or aerosols, along with basic PPE such as gloves, a lab coat, and eye protection. An organism commonly handled at this level is Staphylococcus aureus, which is pathogenic but not primarily spread through the air. At the BSL-3 level, containment is much more stringent because the work involves pathogens that can cause serious disease through inhalation. Features include a negative-pressure room to prevent contaminated air from escaping, directional airflow to keep air moving from clean to work areas, sealed penetrations to avoid leaks, and respiratory protection such as respirators. A typical example is Mycobacterium tuberculosis, which requires this higher level of containment due to its airborne transmission potential. The other options misstate these fundamentals—for instance, assigning negative pressure to BSL-2 or claiming no PPE is used at BSL-2, which is incorrect, or suggesting office settings for BSL work, which does not apply.

Containment levels rise with the degree of engineering controls and protective gear used. At the BSL-2 level, the focus is on standard lab safety with restrictions on access, routine biosafety practices, and the use of a biological safety cabinet for procedures that could generate splashes or aerosols, along with basic PPE such as gloves, a lab coat, and eye protection. An organism commonly handled at this level is Staphylococcus aureus, which is pathogenic but not primarily spread through the air.

At the BSL-3 level, containment is much more stringent because the work involves pathogens that can cause serious disease through inhalation. Features include a negative-pressure room to prevent contaminated air from escaping, directional airflow to keep air moving from clean to work areas, sealed penetrations to avoid leaks, and respiratory protection such as respirators. A typical example is Mycobacterium tuberculosis, which requires this higher level of containment due to its airborne transmission potential.

The other options misstate these fundamentals—for instance, assigning negative pressure to BSL-2 or claiming no PPE is used at BSL-2, which is incorrect, or suggesting office settings for BSL work, which does not apply.