Sewage backups are considered serious biohazards and should be handled with caution. This type of water can carry diseases and bacteria that can lead to very serious illness. Therefore, special equipment and training is needed to clean up properly.
Types of water contamination:
Ex: Broken water line
Ex: Dishwasher overflow, washing machine overflow, etc.
Ex: Sewer backup, flooding rivers, standing water that supports microbial growth