This page houses the Need-to-Know criteria for WPI’s new 2025 exams. To access past Need-to-Knows (NTKs), please refer to this page.
Please get in touch with the certifying authority for your state, province, or geopolitical region to determine which exam preparation materials are appropriate for your jurisdiction and exam date.
The Need-to-Know Criteria documents may only be reproduced with written permission from testing@gowpi.org
Standardized Water Treatment Operator Need-to-Know
- WPI Standardized Water Treatment Operator Class I
- WPI Standardized Water Treatment Operator Class II
- WPI Standardized Water Treatment Operator Class III
- WPI Standardized Water Treatment Operator Class IV
Standardized Water Distribution Operator Need-to-Know
- WPI Standardized Water Distribution Operator Class I
- WPI Standardized Water Distribution Operator Class II
- WPI Standardized Water Distribution Operator Class III
- WPI Standardized Water Distribution Operator Class IV
Standardized Wastewater Collection Operator Need-to-Know
- WPI Standardized Wastewater Collection Operator Class I
- WPI Standardized Wastewater Collection Operator Class II
- WPI Standardized Wastewater Collection Operator Class III
- WPI Standardized Wastewater Collection Operator Class IV
