Skip to main content
King County logo
  1. Professionals and certifications
  2. Certificates of competency

Certificates of Competency

Only individuals with Certificates of Competency are authorized to perform work and maintenance on on-site sewage systems.

Exams for Certificates of Competency

The following dates have been scheduled for Certificate of Competency exams:

  • February 18, 2021
  • June 10, 2021
  • October 14, 2021

In order to sit for a certificate of competency exam, the completed application must be submitted with the fee and proof of applicable education and experience (7) business days prior to the exam date. All exams will be held at the Eastgate Public Health office beginning at 8 AM. Please allow two weeks for grading and announcing the exam results.

Orientation interviews will be scheduled for successful candidates for the Associate Installer, Master Installer, and On-site System Maintainer Certificates of Competency.

Certificates of Competency by profession

A sewage system Designer or Professional Engineer analyzes the property and the soil to determine the appropriate type of sewage system. This includes written plans, construction observation and submission of applications for permit approval or release.
A Master Installer is authorized to install or repair septic systems and 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.

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 confirm 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.

Reference/Study Materials for the Master Installer Certification Exam

Free downloads are available below.

Recommended Standards and Guidance documents (Washington State Dept. of Health):

US Environmental Protection Agency - Onsite Wastewater Treatment and Disposal Systems documents:

 

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.
An Associate Installer is authorized to construct or repair septic systems* and/or directly supervise work crews. The Associate Installer works under the general supervision of a Master Installer.

Qualifications required to become an Associate 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:

  2. Washington On-site Sewage System Association (WOSSA)
    Washington State Environmental Health Association
    Other -- contact Eastgate Public Health for approval
  3. The applicant is required to pass an examination administered by Public Health - Seattle & King County.

  4. The applicant must provide proof that he/she is working under a Master Installer. For example, a letter on company letterhead stating the applicant works for the company.

  5. Examination fee

  6. Annual Certification fee

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 confirm an exam date.

Certificate of competency exam

The closed-book exam will consist of multiple choice, true/false questions and fill-in-the-blank. Results will be mailed to the address indicated on the application. If you fail, you may re-take the exam. A new application form and application and exam fee are required.

Study list for the Associate Installer Exam

Associate Installer applicants must study the King County On-Site Sewage Code, Title 13, Code of the King County Board of Health

Application checklist for Associate Installer Certificate of Competency

  • the installation permit process;
  • requirements for backfill procedure(s)
  • setback requirements;
  • specifications for septic tanks, pump chambers;
  • various drainfield configurations;
  • distribution boxes and sewage piping;
  • soil depth requirements;
  • recommended standards and required procedures for installation and repair of on-site sewage systems

Renewal

  1. At least one continuing education credit (CEU) must be earned during the previous calendar year. Recognized courses are offered by:
  1. Submit Application for Renewal - Certificate of Competency Associate Installer of On-site Sewage Systems (OSS)

  2. Renewal certification fee

Renewal deadlines:

  • Expiration date of the Associate 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 prior to February 4th of the certification year.
  • The exam re-take IS required if the renewal application is received after February 4th of the certification year.
  • A late fee of 25% of the renewal amount ($22.50) will be charged for a renewal application received after January 15th.
  • All fees are non-refundable.
A Liquid Waste Pumper/Hauler is authorized to remove and transfer sewage from septic systems*, portable toilets, grease traps, and vessel holding tanks to a wastewater disposal facility.

Qualifications required to become a Liquid Waste Pumper/Hauler

Business owner responsibilities:

  1. Proof of successful completion of health officer recognized course(s) of instruction in the basic sanitation principles affecting public health, septic system concepts, details of proper servicing of septic tanks or other receptacle of human sewage and transporting and disposing of sewage, septage, sludge or fats, oils and grease. Recognized courses are offered by:
  1. The applicant is required to pass an examination administered by Public Health - Seattle & King County.

  2. The business owner must meet State of Washington minimum bonding requirements and contractors liability.
  1. See current fees.

Pumper employee responsibilities:

  1. Proof of successful completion of health officer recognized course(s) of instruction in the basic sanitation principles affecting public health, septic system concepts, details of proper servicing of septic tanks or other receptacle of human sewage and transporting and disposing of sewage, septage, sludge or fats, oils and grease. Recognized courses are offered by:
  2. The applicant is required to pass an examination administered by Public Health - Seattle & King County.

  3. See current fees.

Application

New business:

After successful completion of training courses, submit the following applications with the appropriate support documents and fees:

Public Health - Seattle & King County will schedule an exam date after the application is reviewed.

Existing business with new pumper employee:

After successful completion of training courses, submit the following application with the appropriate support documents and fee:

Public Health – Seattle & King County will schedule an exam date after the application is reviewed.

Certificate of Competency Exam

The closed-book exam will consist of multiple choice, true/false questions and fill-in-the-blank. Results will be mailed to the address indicated on the application. If you fail, you may re-take the exam. A new application form and application and exam fee are required.

Checklist for Pumper and/or Liquid Waste Hauler Certificate

  • Business Owner Application for Certificate of Competency
    To be completed by the business owner.

  • Pumper Employee Application for Renewal of Certificate of Competency
    A separate application for renewal is required for the pumper employee (i.e. any employee who services OSS sewage tanks and/or transports sewage). The completed application is to be signed by the business owner.

  • Completion of at least 1 annual Continuing Education Unit (CEU)
    The business owner and OSS pumper employees must complete at least 8 contact hours of participation in an organized educational experience acceptable to the health officer pertaining to on-site sewage treatment and disposal.

  • Liquid Waste Vehicle Inspection Report
    All vehicles must pass inspection per code requirements.

  • Disposal Site Authorization Letter
    The business owner must obtain written approval from the waste receiving authority. (Note: For pumpers that use only the Renton Treatment Plant for liquid waste disposal, the authorization may be applied for via the vehicle inspection process.)

  • Labor and Industries specialty or general contractor's license

    State of Washington minimum bonding requirements and contractors liability is required for the pumping business owner/firm. Contact Information:

    Department of Labor and Industries
    Contractor Registration Section
    P.O. Box 44450
    Olympia WA 98504-4450

    Phone 360-902-5226
    Fax 360-902-5228

  • Monthly pumping reports
    Reports must be current (i.e. up to date).

  • See current fees.

Renewal

Submit the following:

Renewal deadlines:

  • Expiration date of the Liquid Waste Pumper/Hauler Certificate of Competency is DECEMBER 31st OF EACH YEAR.
  • Applications for renewal will be accepted annually beginning in December of each year.
  • A late fee of 50% of the renewal amount will be charged for a renewal application received after January 15th. After January 31st, double the renewal fee will be charged and after February 10th passing the competency exam is required.
  • All fees are non-refundable.
An On-site System Maintainer (OSM) is authorized to perform septic inspections and/or preventive maintenance service (including limited repairs) on septic systems*. He/she regularly submits Operation/Performance Monitoring Report forms to Public Health—Seattle & King County.

Qualifications required to become an On-site System Maintainer

Application

After successful completion of training courses, submit an Application for On-site System Maintainer to Public Health with the appropriate support documents and fee. After the application is reviewed, Public Health will confirm an exam date.

Certificate of Competency Exam

The Maintainer Competency Exam covers all aspects relating to the operation, problem diagnosis and maintenance 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 4 hours to complete the exam. The exam will consist of multiple choice and true/false questions. 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, a letter will be included with the exam results requesting:

  • A copy of proof of performance bond (i.e. specialty or general contractor's license)
  • OSM Certificate of Competency fee (See current fees)

IF YOU FAIL, you may schedule a re-take of the exam on the next scheduled exam date. A new application form and exam fee will be required.

Checklist

Renewal

  1. At least one continuing education credit (CEU) must be earned by the business owner and septic system pumper employees during the previous calendar year. Recognized courses are offered by:
  2. Attendance at all mandatory informational/educational meetings held by Public Health—Seattle & King County.

  3. Submit Application for Certificate of Competency On-site System Maintainer.

  4. Proof of State of Washington minimum bonding requirements and contractors liability:
  5. Renewal certification fee (See current fees)

Deadlines

  • Expiration date of the OSM Certificate of Competency is DECEMBER 31st OF EACH YEAR. The OSM may not conduct performance monitoring inspections or preventive maintenance of OSS after December 31st unless the certification has been renewed.
  • Applications for renewal will be accepted annually beginning in mid-November.
  • The exam re-take IS NOT required if the renewal application is received prior to 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.