How must sewage be disposed of in cosmetology establishments?

Sewage disposal in cosmetology establishments must be conducted through an approved sewage disposal system to ensure public health and safety. This requirement is in place to prevent contamination of water sources and to maintain sanitary conditions within the facility. Using an approved sewage disposal system means that the establishment complies with local regulations and standards set to manage waste effectively and safely. Such systems are designed to treat sewage properly before it enters the environment, minimizing the risk of pollution and health hazards.

Other methods of disposal, like those mentioned in the incorrect options, do not meet health and safety standards. For example, using any available drainage system could lead to unregulated disposal, which may not be safe or legal. Portable sanitation units are generally used in temporary or outdoor situations rather than being a primary method for sewage disposal in permanent facilities. Moreover, dumping sewage into local waterways poses significant environmental threats, including water pollution and the spread of diseases, making it a prohibited practice.