Washington State

House of Representatives

Office of Program Research



Labor & Workplace Standards Committee

SB 6170

This analysis was prepared by non-partisan legislative staff for the use of legislative members in their deliberations. This analysis is not a part of the legislation nor does it constitute a statement of legislative intent.

Brief Description: Concerning plumbing.

Sponsors: Senators Keiser, Conway, Fortunato, Hasegawa and King.

Brief Summary of Bill

  • Establishes requirements for a plumbing contractor license.

  • Creates a residential service plumbing certificate.

  • Modifies the acceptable supervisory ratios of plumber trainees to certified plumbers and authorizes remote supervision in certain circumstances.

  • Increases the number of members on the Advisory Board of Plumbers.

Hearing Date: 2/20/20

Staff: Lily Smith (786-7175).


Plumbing Training and Certification Requirements.

The Department of Labor and Industries (Department) administers and enforces the plumbing trade laws. A plumbing contractor must register as a contractor under laws applicable to construction generally, and a plumber must be certified as either a journey level or specialty plumber. Specialties are residential, backflow, and domestic pump.

To obtain a plumbing certificate, persons meet certain experience and education requirements and pass an exam. For a journey level plumber, the individual must have four years experience working under the direct supervision of a journey level plumber. The experience required for specialty plumbers depends on the specialty. A medical gas piping installer endorsement authorizes a journey level plumber to install medical gas piping. To receive the endorsement, an individual must have completed or be enrolled in a medical gas piping training course.

Plumbing certificates of competency must be renewed every other year. To renew a certificate of competency, the applicant must complete 16 hours of continuing education, including four hours related to electrical safety.

Plumber Trainees.

Persons gaining the required experience must obtain a training certificate. Trainees must work under the direct supervision of a journey level or specialty plumber working in that plumber's specialty, or certified medical gas piping installer, as appropriate. Supervision means the person is on the same job site and under the control of a certified plumber at least 75 percent of each working day for journey level and specialty plumbing. Supervision must be 100 percent of the time for medical gas piping. The ratio of trainees to certified plumbers is 1:1 for journey level plumbing and medical gas piping installation and 2:1 for specialty plumbing.

State Advisory Board of Plumbers.

A State Advisory Board of Plumbers (Board) conducts hearings on revocation and suspension of certificates. The Board must consent to any contract the Department enters into for the development and administration of required examinations, and otherwise advises the Department on all matters relative to the plumbing provisions. The Board consists of seven members: two journey level plumbers, one specialty plumber, three members conducting a plumbing business, and one public member familiar with the business and trade of plumbing. The Director of the Department appoints the members.

Summary of Bill:

Plumbing Contractors.

A contractor engaging in plumbing work is subject to new provisions and licensing requirements specifically for plumbing contractors, instead of the general contractor registration requirements for all construction.

It is unlawful to advertise, offer to do work, submit a bid, or perform any plumbing work without being licensed as a plumbing contractor. In addition to other plumbing contractor license application requirements, such as providing the location of the business and proof of workers' compensation, an applicant for a plumbing contractor license must employ a full-time individual who currently possesses a valid journey level or specialty plumber's certificate of competency. Plumbing contractor applicants must file a surety bond and provide proof of insurance or financial responsibility with the Department. A plumbing contractor license expires two years after the date of issuance.

A plumbing contractor is required to ensure all plumbing work complies with the certification laws and rules of the state and is performed by properly licensed plumbing individuals, except for work on their own residence.

Plumbing contractors must report plumbing trainee hours worked and provide information to the Department related to work supervision. Failure to have or maintain payroll and other records for each employee performing plumbing work for the company is subject to the issuance of an infraction and a penalty of up to $5,000. Records must be maintained for three years.

Residential Service Plumbing.

A residential service plumbing certificate is established. A residential service plumber performs residential service plumbing in an existing residential structure, and is limited to certain service, repair, replacement, or cleaning work. A residential service plumber may not perform plumbing for new construction of any kind.

A residential service plumber may supervise a plumbing trainee if the trainee was supervised by an appropriate journey level or specialty plumber for the trainee's first 2,000 hours.

To be eligible to take an examination for a certificate of competency, applicants for a residential service plumber certificate must furnish evidence of completion of a qualified course of study in the plumbing trade, or have two or more years of experience under specified supervision.

Continuing Certificate and License Requirements.

Certificates of competency must be renewed every three years, rather than every other year. For renewal, the applicant must complete 24, rather than 16, hours of continuing education.

A plumbing certificate, license, or endorsement may be suspended, revoked, or subject to civil penalty for one or more of the following:

Plumber Trainees.

A "plumber trainee" is defined as a person with a plumbing training certificate but not a certificate of competency. A trainee may perform plumbing work if under the appropriate level of supervision.

Remote supervision of trainees working on service plumbing in a residential structure is authorized in circumstances meeting certain criteria.

Until December 31, 2025, the ratio of trainees to certified journey level, residential service, or specialty plumbers working on a job site must not be more than:

After December 31, 2025, no more than two trainees may work on any residential structure job site for every certified specialty plumber or journey level plumber working as a specialty plumber.

Advisory Board of Plumbers.

The number of members on the Advisory Board of Plumbers (Advisory Board) is changed from seven to nine. Members representing the state-approved plumbing code body and the Department of Health are added. The Advisory Board must generally advise the Department on all matters relative to the enforcement of the plumbing laws, plumbing industry promotion, standards of plumbing installations, consumer protection, and standards for the protection of public health.

The Department must instruct the Advisory Board to convene a subgroup after the 2023 legislative session, the 2024 legislative session, and every three years after to evaluate the effects trainee ratio changes have on the industry, including public safety and industry responses to public demand for plumbing services. The subgroup must determine a sustainable plan for maintaining sufficient numbers of plumbers and trainees within the plumbing workforce to safely meet the needs of the public. A report is due to the standing labor committees of the Legislature by December 1st of each year the subgroup convenes. The subgroup includes:

Infractions, Penalties, and Appeals.

A person found to have engaged in the trade of plumbing without having a valid certificate must be assessed a minimum penalty of $100 for the first infraction. A contractor found to have engaged in the trade of plumbing without a valid plumbing contractor license must be assessed a minimum monetary penalty of $500 for the first infraction. The maximum penalty for engaging in the trade of plumbing without an appropriate certificate or license is $5,000 for a second or subsequent infraction.

The Director of the Department, instead of an administrative law judge, may waive or reduce collection of payment for good cause. An individual or a contractor who acquires three infractions in three years may have their certificate, license, endorsement, or registration suspended for up to two years upon recommendation of the Advisory Board.

Appeals of infractions must be made within 20 days of service of the infraction and must be accompanied by a certified check for $200. The check must be returned to the assessed party if the Department's decision is not sustained. If the final decision sustains the Department's determination, the Department must apply the $200 to the payment of expenses of the appeal, including costs charged by the Office of Administrative Hearings.

Plumbing Permits.

No city, town, or county may issue a plumbing permit for work to be done by a plumbing contractor without verification the contractor is currently licensed. The contractor license number must be printed on the permit. Notice must be provided to the permit applicant of the plumbing contractor license laws and the potential risk and liability to the homeowner for using an unlicensed plumbing contractor. A plumbing permit with a licensing exemption obtained with falsified information is forfeited.


The definition of "plumbing" is modified to incorporate definitions used in the plumbing code as adopted by the Washington State Building Code Council. The definition of "medical gas piping" is modified to include other medical gas or equipment in addition to the gases and equipment previously listed. Definitions for "plumbing contractor," "plumber trainee," "residential service plumber," and "unsatisfied final judgment" are added.

Appropriation: None.

Fiscal Note: Available.

Effective Date: The bill takes effect 90 days after adjournment of the session in which the bill is passed, except for sections 21, 22, and 28, relating to dual registrations of general and electrical contractors, incidental plumbing work by electricians, and local permits, which take effect January 1, 2021, and section 26, relating to specialty electrician training, which takes effect July 1, 2023.