What are the two types of cleanroom filters?

The correct answer highlights the two primary types of cleanroom filters, which are essential in maintaining the stringent air quality required in cleanroom environments. Roomside replaceable ceiling modules are designed to allow for easy access and replacement without disrupting the cleanroom environment significantly. This feature is crucial for maintaining cleanliness and operational efficiency since cleanrooms often need to limit disturbances that could introduce contaminants.

Fan powered modules are another type of cleanroom filter that incorporates a fan to assist in air circulation, enhancing the efficiency of filtration by actively moving air through the filter rather than relying solely on passive airflow. These modules help ensure that the air quality meets specific standards by providing effective filtration while also controlling airflow within the cleanroom.

While HEPA (High Efficiency Particulate Air) filters and ULPA (Ultra-Low Penetration Air) filters are critical for cleanroom applications, the question specifically asks for types of cleanroom filters rather than classification of filtration efficiency. Pre-filters and final filters, as well as activated carbon and electronic filters, serve specific functions but do not capture the primary filtering solutions used in cleanroom applications as effectively as the options noted in the correct answer.