1. Reason for revision and main contents

It is intended to change the name of fine dust (PM-2.5) to ultrafine dust (PM-2.5) in the relevant item of the indoor air quality maintenance standards and to strengthen the indoor air quality maintenance standards for ultrafine dust in museums, art galleries, large-scale stores, and academies that are used by many people, including children and juveniles, from 50 ㎍/㎥ or less to 40 ㎍/㎥ or less, in order to protect public health.