ACTIVATED SLUDGE. About 100 years ago, engineers noticed that re-suspension and re-aeration of the settled sludge from secondary clarifiers in a fresh.
Ethylene Oxide Training on the hazards of ethylene oxide (EtO) in the workplace Developed by the Division of Occupational Safety & Health (DOSH) for employee.
By: Angel Bellace, Mike Merlino & Christian Snowden.
