Installer Test Instructions

Installers may complete their Installer Test and obtain their Installer Certification through Northeast Tri County Health District. 

Study Materials

These materials may be reviewed online or if you do not have internet access paper copies can be provided for a $72.15 fee. Please contact our office to request the materials. 

• Northeast Tri County Health District On-Site Sewage Regulation 01-2007
• Alternating Drainfields Standards & Guidance
• Dosing Gravity Standards & Guidance
• Gravelless Drainfields Standards & Guidance
• Gravity Flow On-Site Sewage System Standards & Guidance
• Holding Tank Standards & Guidance
• Intermittent Sand Filter Standards & Guidance
• Mound System Standards & Guidance
• OSS Construction Guide & Specification Sheet
• OSS Design Checklist
• Pressure Distribution System Standards & Guidance
• Proprietary On-Site Wastewater Treatment Products Standards & Guidance
• Recirculating Gravel Filter Standards & Guidance
• Sand Lined Trench Systems
• Stratified Sand Filter Treatment Systems Standards & Guidance
• Subsurface Drip System Standards & Guidance
• Water Conserving On-Site Wasterwater Treatment Systems Standards & Guidance

Taking The Test

• Call the Environmental Health office in the county where you wish to take the test to make an appointment. 
• Pay test fee. (This fee will be deducted from the new installer fee if a passing score is achieved.)
• Allow 2 to 3 hours for taking the test.
• The test is closed book. Study materials, such as notes or guidelines, cannot be used while taking the test. 

Scoring The Test

• The test will be reviewed and scored by the Environmental Health Supervisor or Director.
• Passing score is 80% or better. 
• If a passing score is obtained on the installer test, refer to the next section "Obtaining an Installer Certificate". 
• If a passing score is not achieved on the test, an appointment may be made to retake the test.  A one-week wait will be required before an appointment will be scheduled and a retest fee must be submitted prior to retaking the test. An applicant will only be allowed to take the test 3 times. Any further request for testing after three attempts must be approved by the Director of Environmental Health. 

Obtaining An Installer Certificate

• Upon successfully passing the test, an application for an installer certificate must be completed and returned to the Environmental Health office along with the new installer fee (minus the test fee.)
• A copy of a current contractor license issued by the Department of Labor and Industries (L&I) will be required before a certificate can be issued. 
• Installer certificates are valid from May 1st to April 30th and the fee will not be prorated. 
• If the installer application, fee and L&I license are not submitted to the Health District within 6 months after passing the test, the test will be invalid, and the applicant will be required to retake the installer test to obtain an installer certificate. A retest fee will be required before retaking the test. 
• An installer having more than a ninety day lapse in renewal from the expiration date on their last valid certificate, must take and pass the test to obtain a new installer certificate.