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Certificates of competency - Master Installer

A Master Installer is authorized to install or repair septic systems*. The Master Installer also obtains the proper installation and repair permits from Public Health - Seattle & King County. The Associate Installer works under the general supervision of the Master Installer.

Qualifications required to become a Master Installer
  1. Proof of successful completion within the previous 12 months of a health officer recognized course of instruction in the basics of septic systems and installation of septic systems. Recognized courses are offered by:
  1. The applicant is required to pass an examination administered by Public Health — Seattle & King County.
  2. The applicant or his/her employer must meet State of Washington minimum bonding requirements and contractors liability. To obtain a performance bond, you need a specialty or general contractor's license.
  1. Examination and Annual Certification fees (Call Environmental Health at 206-263-9566 for current fee costs.)
Application

After successful completion of training courses, submit an Application for Installer Certificate of Competency (for Associate and Master Installers) to Public Health with the appropriate support documents and fee. After the application is reviewed, Public Health will schedule an exam date.

Certificate of Competency Exam

The Master Installer Certificate of Competency Exam covers all aspects relating to installation, repair and design of septic systems. It includes, but is not limited to, an extended knowledge of the following:

The exam is closed book and applicants are given 3-1/2 hours to complete the exam. The exam will consist of multiple choice, true/false questions, fill-in-the-blank, and calculation problems. A self-powered, non-printing, non-programmable, non-text calculator is allowed. Results will be mailed to the address indicated on the application.

IF YOU PASS THE EXAM, a post-exam oral interview will be scheduled. It will review the exam results and additional applicant knowledge.

IF YOU FAIL THE EXAM, you may re-take the exam. A new application form and application and exam fee are required.

Renewal
  1. At least one continuing education credit (CEU) must be earned during the previous calendar year. 1 CEU = 8 contact hours (Note: more than one class may be necessary to meet this requirement). Recognized courses are offered by:
  1. Submit Application for Renewal of Certificate of Competency Master Installer of On-site Sewage Systems (OSS)

  2. Proof of State of Washington minimum bonding requirements and contractors liability.
  1. Renewal certification fee (Call Environmental Health at 206-263-9566 for current fee costs.)
Deadlines
  • Expiration date of the Master Installer Certificate of Competency is DECEMBER 31st OF EACH YEAR.
  • Applications for renewal will be accepted annually beginning in December of each year.
  • The exam re-take IS NOT required if the renewal application is received on or before January 15th of the certification year.
  • The exam re-take IS required if the renewal application is received after January 15th of the certification year.
  • A late fee of 25% of the renewal amount will be charged for a renewal application received after January 15th.
  • All fees are non-refundable.