OWP will be closed from 4:00 pm on Friday, December 20, 2024, until 8:00 am on Thursday, January 2, 2025, for Winter Break.
(All times are PST.)
For students in Canada: Due to the ongoing Canada Post strike, please use UPS or FedEx to return your scantrons for grading. You may take your exams online even if you received paper exams.
If exams are submitted: |
Course certificates will be mailed: |
By December 13th |
By December 20th |
After December 20th |
Early January |
Please note: Postmark dates will not be honored.
Water and Wastewater Terms Beginning U
A B C D E F G H I J K L M N O P Q R S T U V W Y Z
ultraviolet (UV)
Pertaining to a band of electromagnetic radiation just beyond the visible light spectrum used in water and wastewater treatment for disinfection. When ultraviolet radiation is absorbed by the cells of microorganisms, it damages the genetic material in such a way that the organisms are no longer able to grow or reproduce, thus ultimately killing them.