According to the table on bsl’s, hepa filters for exhaust air are absolutely required at BSL4.
A biosafety level (BSL), can be regarded as the pathogen/protection level, and these are the biocontainment precautions that is needed to be kept so that harmful agent can be get rid of.
Therefore at , exhaust air are absolutely required at BSL4 because it is needed to isolate dangerous biological agents.
Learn more about biosafety level at: https://brainly.com/question/8430576
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