What is a characteristic of a Class II Biological Safety Cabinet?

A Class II Biological Safety Cabinet is indeed divided into subtypes based on air circulation, which is a critical feature that distinguishes it from other safety equipment. These subtypes are commonly referred to as Class II A, B1, B2, and B3, each designed to provide varying levels of airflow and containment for specific types of work. This classification allows users to select a cabinet that best fits their specific needs for protection of the operator, the environment, and the product being manipulated.

This characteristic is essential because it ensures that the cabinet can handle a variety of substances and procedures while maintaining safety standards. The subtypes vary in terms of how they recirculate air, filter particulate matter, and protect against contamination, thus making them versatile and highly functional in laboratory settings.