Washington State Department of Labor & Industries (L&I), Plumber Certification Program administers plumber licensing in Washington. Every figure below is verified against the board’s own official pages and dated. Who must personally hold a credential — the contractor, the business, or the individual worker — is set out under Requirements.
What it’s called
Washington does not call the individual credential a license: the Department of Labor & Industries issues a certificate of competency (journey level, residential specialty, residential service, pump and irrigation, domestic pump or backflow specialty), a plumber trainee certificate, and a medical gas piping installer endorsement, and RCW 18.106.020(1) requires the individual to hold one. Someone searching for a Washington plumbing license or a journeyman plumber license is looking for these certificates; the official level is journey level plumber (PL01), and chapter 18.106 RCW has no master plumber tier. There is no separate state plumbing board – the Plumber Certification Program sits inside L&I, advised by the Advisory Board of Plumbers. L&I itself uses “plumbing license” for the BUSINESS credential (“Not maintaining your plumbing license can result in penalties ranging from $500.00 to $5,000”): since July 1, 2021 a firm doing plumbing work needs a plumbing contractor license under RCW 18.106.400, which replaced the old specialty plumbing contractor registration under chapter 18.27 RCW.
License types & fees
| Type | Experience | Exam | Fee |
|---|---|---|---|
| Plumber Trainee Certificate (PT00; PT31 for backflow) -- the entry credential, and the clock-starter | None to apply. L&I lists what plumber trainees must do: "Apply for a plumber trainee certificate," "Be 16 or older," "Work under the direct supervision of a journey level or certified plumber," and "Have an electrical trainee card if working in the pump and irrigation or domestic pump trade." WAC 296-400A-120(1)(d): "All applicants for a plumbing trainee certificate must be at least 16 years of age and must follow requirements as defined in WAC 296-125-030." The original card is one-time: "If an individual has previously held a plumbing trainee certificate, then that individual is not eligible for a subsequent original trainee certificate" (WAC 296-400A-120(1)(c)). By statute "All apprentices and individuals learning the plumbing construction trade shall obtain a plumbing training certificate from the department," and "The holder of the plumbing training certificate shall renew the certificate annually" (RCW 18.106.070(2)). Hours count only on an active card: "Plumber trainee hours accumulated in the state of Washington will be credited only if an active Washington state trainee card was in place when the work occurred" (WAC 296-400A-110). A PT31 certificate is required to work as a backflow specialty plumber under supervision, and "PT31 trainee requires one hundred percent supervision" (WAC 296-400A-010(4)). | None. | $60.00 to apply and $60.00 to renew each year (L&I Plumber Trainee page; WAC 296-400A-045 "Trainee certificate" $60.00; Application for Plumber Trainee Certification F627-003-000, revised 07-2026). |
| Journey Level Plumber Certificate of Competency (PL01) | L&I: "Four years or more (at least 8,000 hours) working as a plumber trainee under the supervision of a certified journey level plumber," of which "Two years or more (at least 4,000 hours) must be spent working in commercial or industrial installations." WAC 296-400A-121(1): "You may take the journey level examination after completing 8,000 hours and not less than four years of documented training which must include 4,000 hours of commercial plumbing experience under direct supervision of a certified journey level plumber." The statute offers an alternative route: written evidence that the applicant "has completed a course of study in the plumbing trade in the armed services of the United States or at a school accredited by the workforce training and education coordinating board, or has had four or more years of experience under the direct supervision of a certified journey level plumber" (RCW 18.106.040(1)(a)); but "No more than fifty percent of the minimum work experience needed to qualify for plumbing certification is allowed for any training school program" (WAC 296-400A-100(3)). Before testing, "Individuals are required to complete 16 hours of continuing education with a minimum of 4 hours of industry related electrical training prior to testing for journey level, domestic pump, or residential specialty plumber certification" (WAC 296-400A-121(6)). Scope: "A journey level plumber may work on all phases of plumbing projects including residential, commercial and industrial worksite locations" (WAC 296-400A-010(1)). | Washington Journey Level plumber examination, administered by PSI after L&I approves eligibility; closed book, in three parts -- 100 plumbing code questions, a waste-and-vent sizing exercise and a water-pipe sizing exercise (L&I Plumber Examination page; Plumber Exam Application F627-008-000, revised 07-2026). | $202.10 exam application (non-refundable) plus a separate PSI scheduling fee whose amount L&I does not publish; $242.70 certificate fee on passing; $242.70 three-year renewal (WAC 296-400A-045; L&I Get or Renew page; F627-008-000; F627-019-000, revised 07-2026). |
| Residential Specialty Plumber Certificate of Competency (PL02) | L&I: "3 years or more (at least 6,000 hours) working in the specialty under supervision of a certified residential or journey level plumber." WAC 296-400A-121(2): "You may take the residential specialty plumber examination after completing 6,000 hours and not less than three years of documented training under direct supervision of a certified residential specialty or journey level plumber." RCW 18.106.040(1)(b) alternatively accepts a course of study in the plumbing trade in the armed services or at a school licensed by the workforce training and education coordinating board under chapter 28C.10 RCW. The 16 hours of pre-exam continuing education (minimum 4 hours industry-related electrical) applies (WAC 296-400A-121(6)). Scope: "limited to installation, maintenance, and repair of plumbing in single-family dwellings, duplexes, and apartment buildings which do not exceed three stories" (L&I). | Residential Specialty examination (PSI); closed book, with the same three-part structure as the Journey Level exam (L&I Plumber Examination page). | $202.10 exam application; $242.70 certificate; $242.70 three-year renewal (WAC 296-400A-045). |
| Residential Service Plumber Certificate of Competency (PL04) | L&I: "Two years or more (at least 4,000 hours) working as a plumber trainee under the supervision of a journey level, residential specialty, or residential service certified plumber," and "Your first year or more (at least 2,000 hours) must be spent working under the direct supervision of a journey level or residential specialty plumber." WAC 296-400A-121(3): "The first year and 2,000 hours of supervision must be under direct supervision of a certified journey level or residential specialty plumber. The second year and 2,000 hours of trainee could be under a residential service plumber." Scope (RCW 18.106.010(11)): in single-family dwellings and duplexes only, a residential service plumber may service, repair, or replace previously existing fixtures, piping, and fittings that are outside the interior wall or above the floor; in any residential structure may perform plumbing work as needed for drain cleaning and leak repairs on any pipe, fitting, or fixture "from the leak to the next serviceable connection"; and "A residential service plumber may not perform plumbing for new construction of any kind." | Residential Service specialty examination (PSI): "This exam contains questions taken from UPC with amendments, mechanical code with amendments, RCWs and WACs and other related sources" (L&I Plumber Examination page). | $202.10 exam application; $242.70 certificate; $242.70 three-year renewal (WAC 296-400A-045). |
| Pump and Irrigation Specialty Plumber (PL03) and Domestic Well / Limited Volume Domestic Pump Specialty Plumber (PL03A) | L&I: PL03 requires "2 years or more (at least 4,000 hours) working in the specialty under supervision of an appropriate certified plumber (excluding PL03A and PL30)"; PL03A requires "1 year or more (at least 2,000 hours) working in the specialty under supervision of a certified plumber, (excluding PL30)." The statute sets "one year of practical experience working on pumping systems not exceeding one hundred gallons per minute, and two years of practical experience working on pumping systems exceeding one hundred gallons per minute, or equivalent as determined by rule by the department in consultation with the advisory board" (RCW 18.106.040(1)(d)); WAC 296-400A-121(4) sets one year and 2,000 hours for the limited volume specialty and 4,000 hours but not less than two years for the unrestricted specialty, and adds: "Restricted domestic pump specialty trainees who have completed at least 720 hours of on-the-job training and passed the competency examination required by WAC 296-400A-020 may work unsupervised for the remainder of the time required for work experience to become a restricted domestic pump specialty plumber" (WAC 296-400A-121(4)(a)). L&I: "Working in this trade also requires electrical certification." L&I describes PL03A as limited to a pump "not exceeding 100 gallons per minute or 7.5 horsepower, single phase"; the rule's definition states only the 100 gallons-per-minute limit (WAC 296-400A-010(6)). | Domestic Pump / Pump and Irrigation specialty examination (PSI): "This exam contains questions taken from Chapters 2, 3, 6, and 16 of the UPC and amendments" (L&I). WAC 296-400A-045 says the domestic pump specialty examination fee is paid directly to a nationally recognized testing agency, and with advisory board approval the department may accept a certification issued by a professional trade association in lieu of its application and examination steps (WAC 296-400A-020(1)(g)). | $202.10 application (valid one year); $242.80 certificate; $242.80 three-year renewal (WAC 296-400A-045; F627-008-000; F627-019-000). One L&I page still prints older amounts -- see Fees. |
| Backflow Specialty Plumber -- backflow assembly maintenance and repair (PL30) | No years of employment. L&I: "An active BAT (Backflow Assembly Tester Certification) issued by the Washington State Department of Health is required"; WAC 296-400A-121(5) requires written evidence of a valid backflow assembly tester certification. The specialty covers maintenance and repair of backflow assemblies within a building and "does not include installing or replacing backflow prevention assemblies" (L&I). "Experience obtained as a backflow assembly maintenance and repair specialty may not be applied toward journey level or specialty plumber certification" (WAC 296-400A-100(5)). | Backflow specialty examination: "This exam contains questions relating to safety, regulatory, operation, and troubleshooting of backflow prevention assemblies" (L&I Plumber Examination page). | $202.10 examination application; $167.40 certificate and three-year renewal (WAC 296-400A-045; L&I Get or Renew page). No continuing education; renewal requires a current Department of Health BAT certification. |
| Medical Gas Piping Installer Endorsement (MG01) -- added to a Washington journey level certificate | WAC 296-400A-021: "Only journey level plumbers holding active state of Washington certification may apply for this endorsement." L&I: "Must complete at least 32 hours of training in an L&I approved medical gas training course." RCW 18.106.020(2): "Without exception, no person may engage in or offer to engage in medical gas piping installation without having a certificate of competency as a journey level plumber and a medical gas piping installer endorsement and photo identification in his or her possession." | "Pass the written and practical competency examination provided by a nationally recognized testing agency under contract with the department" (WAC 296-400A-021(4)); the medical gas examination fee is paid to that testing agency, not to L&I (WAC 296-400A-045). | $74.30 endorsement application; $166.90 endorsement fee and three-year renewal (WAC 296-400A-045; L&I Get or Renew page). The training course fee is paid to the approved course provider. Renewal requires affidavits of continuity showing brazing every six months (WAC 296-400A-022). |
| Temporary Permit (out-of-state journey level, residential specialty or domestic pump specialty plumbers only) | An active state-issued journey level, domestic pump specialty or residential specialty certificate; sufficient qualifying evidence; never having taken that Washington competency examination; and not being a trainee or apprentice plumber (WAC 296-400A-031). "Temporary permits are not issued for installers of medical gas piping systems" or for the backflow specialty (WAC 296-400A-030). L&I: "If you have ever held a temporary permit, or a Washington state plumber or trainee certification, you are not eligible for a temporary permit." | None for the permit itself; it covers the period before the Washington examination, and no temporary permit is issued to "Any person who has failed to pass the examination for a certificate of competency" (RCW 18.106.090(1)). | $100.30 permit plus the $202.10 examination application fee (WAC 296-400A-032 and -045; L&I Plumber Examination page). Duration: WAC 296-400A-033 says "A temporary permit is valid for four months and is nonrenewable"; the fee table in WAC 296-400A-045 and L&I's examination page state 120 days. |
Who does NOT need this license — exemptions
Washington’s exemptions are in RCW 18.106.150, quoted here in full. (1) “Nothing in this chapter shall be construed to require that a person obtain a license in order to do plumbing work at his or her residence or farm or place of business or on other property owned by him or her.” (2) “A current certificate of competency or apprentice permit is not required for: (a) Persons performing plumbing work on a farm; or (b) Certified journey level electricians, certified residential specialty electricians, or electrical trainees working for an electrical contractor and performing exempt work under: (i) RCW 18.27.090 (18) until January 1, 2021; (ii) After January 1, 2021, under subsection (8) of this section.” (3) “Nothing in this chapter shall be intended to derogate from or dispense with the requirements of any valid plumbing code enacted by a political subdivision of the state, except that no code shall require the holder of a certificate of competency to demonstrate any additional proof of competency or obtain any other license or pay any fee in order to engage in the trade of plumbing.” (4) “This chapter shall not apply to common carriers subject to Part I of the Interstate Commerce Act, nor to their officers and employees.” (5) “Nothing in this chapter shall be construed to apply to any farm, business, industrial plant, or corporation doing plumbing work on premises it owns or operates.” (6) “Nothing in this chapter shall be construed to restrict the right of any householder to assist or receive assistance from a friend, neighbor, relative, or other person when none of the individuals doing such plumbing hold themselves out as engaged in the trade or business of plumbing.” (7) “This section does not apply to anyone installing, altering, repairing, or renovating medical gas systems.” – so none of the exemptions in this section reaches medical gas work, and RCW 18.106.020(2) separately requires, “Without exception,” a journey level certificate plus the medical gas endorsement for medical gas piping installation. (8) “As of January 1, 2021, nothing in this chapter shall be construed to apply to an entity who holds a valid electrical contractor’s license under chapter 19.28 RCW that employs a certified journey level electrician, a certified residential specialty electrician, or an electrical trainee meeting the requirements of chapter 19.28 RCW to perform plumbing work that is incidentally, directly, and immediately appropriate to the like-in-kind replacement of a household appliance or other small household utilization equipment that requires limited electrical power and limited waste, water connections, or both. An electrical trainee must be supervised by a certified electrician while performing plumbing work.” WAC 296-400A-010(8) illustrates the limit of (8): an electrician performing a like-in-kind replacement of an electric hot water tank “could only disconnect and then reconnect the water supply lines to the tank and drain line from the temperature and pressure relief valve. Gas hot water tanks are not part of the electrician’s exemption.” For (6), the rule defines the term in full (WAC 296-400A-005): “Assist” means “a friend, neighbor, or other person (including a certified plumber) may assist a householder, at his or her residence, in the performance of plumbing work on the condition that the householder is present when the work is performed and the person assisting the householder does not accept money or other forms of compensation for the volunteer work. For the purposes of this subsection, a residence is a single-family residence.” So under the rule, help counts as assistance only when it is unpaid, the householder is present, and the home is a single-family residence. SCOPE LIMITS THAT ARE NOT EXEMPTIONS: L&I states that “Except for domestic pump and pump and irrigation systems, certification is not required to install plumbing systems outside of a building (e.g., water lines connected directly to municipal water mains, sewer line connections, etc.),” consistent with the statutory definition of plumbing as systems “within a building” (RCW 18.106.010(9)). CONTRACTOR LICENSE ONLY: the plumbing contractor license requirement “does not apply to: A person who is contracting for plumbing work on his or her own residence, unless the plumbing work is on a building that is for rent, sale, or lease” (RCW 18.106.400(7)), and a certified plumber who is “an employee of such a licensed plumbing contractor, with wages as their sole compensation” needs no contractor license (WAC 296-400A-430). A city, town, or county may not issue a plumbing permit for work by a contractor required to be licensed without verifying the license, and “If a plumbing permit is obtained by an applicant or contractor who falsifies information to obtain an exemption provided under RCW 18.106.150 the plumbing permit shall be forfeited” (RCW 18.106.440).
Fees
Set by WAC 296-400A-045 (“the department’s nonrefundable fees”), last amended by WSR 26-10-060, filed 5/5/26, EFFECTIVE 7/1/26. INDIVIDUAL CREDENTIALS: trainee certificate $60.00 (one year); examination application for journey level, residential specialty, residential service or backflow certification, or reexamination of a medical gas endorsement, $202.10 per examination; domestic pump specialty application $202.10 (valid one year); reciprocity application $202.10 (valid one year); temporary permit $100.30; journey level, residential specialty or residential service certificate (first card or three-year renewal) $242.70; domestic pump specialty certificate $242.80; backflow assembly maintenance and repair specialty certificate $167.40; medical gas endorsement application $74.30 and endorsement (first card or three-year renewal) $166.90; reinstatement $324.50 (residential and journey level certificates), $186.60 (backflow), $486.00 (domestic pump); unsupervised trainee endorsement $43.30; inactive status fee $43.30; certified letter/verification of licensure $43.30; replacement of any certificate or license $27.20; refund processing $29.20. Examination administration is performed by a state authorized contractor and “The fees for such examinations are set by contract with the department and are additional to the department’s examination fees” (WAC 296-400A-045); L&I says PSI charges a scheduling fee but does not publish its amount. The medical gas endorsement and domestic pump examination fees are paid directly to the testing agency and the medical gas training course fee to the course provider. LATE RENEWAL: “If a person fails to renew the certificate by the renewal date, he or she must pay a doubled fee” (RCW 18.106.070(1)(a)); the official renewal form F627-019-000 (revised 07-2026) lists the late amounts as $485.40 (journey level/residential/residential service), $485.60 (domestic pump/pump and irrigation), $334.80 (backflow specialty) and $333.80 (medical gas). Missing continuing education by the renewal date also triggers the doubled fee (WAC 296-400A-023(5)). PLUMBING CONTRACTOR: license $148.10 “For each issuance, renewal or reregistration of a license” (valid two years); initial identification or change of designated plumber $53.20; reinstatement $74.00; service-of-process fee in a suit against the contractor’s bond $58.50 (WAC 296-400A-045); plus the $6,000 bond and liability insurance. CONTINUING EDUCATION COURSE APPROVAL (providers): $262.70 new course, $131.10 renewal. L&I SOURCES THAT DIFFER FROM THE RULE (recorded as published, none resolved silently): (1) Plumbing contractor RENEWAL – the rule charges $148.10 for issuance and renewal, while L&I’s Plumbing Licensing Requirements page tells contractors to renew with “The required fee of $139.10.” (2) Plumbing contractor REINSTATEMENT – the rule says $74.00; the same L&I page says “Pay the reinstatement fee of $69.50.” (3) RETEST fee – L&I’s Get or Renew page says that after 90 days “A retesting fee of $189.80 will apply along with your certification fee”; the rule, L&I’s examination page and the Plumber Exam Application (revised 07-2026) all charge $202.10 per examination. (4) COMBINATION plumber/electrician page – its step list says “Apply for and pass the plumber exam ($202.10)” and “Pay the plumber certification fee ($242.80),” but lower on the same page it lists “$189.80 for your plumber examination” and $228.00 for the Domestic Pump / Pump and Irrigation certificate and renewal ($456.00 late). The rule effective 7/1/26 and the forms revised 07-2026 carry $202.10 and $242.80.
Exam
L&I decides eligibility; PSI delivers the test. “Plumber Certification exams are administered by PSI, with testing locations available across the United States. Candidates will need to apply for eligibility with the Department before being allowed to take an examination. Approved applications are good for one year” (Plumber Exam Application F627-008-000, revised 07-2026; L&I Plumber Examination page). After approval L&I sends a letter explaining how to contact PSI, and “It is your responsibility to contact PSI to pay and schedule for the examination. There will also be a scheduling fee you will be required to pay to PSI in order to schedule your examination” – L&I does not state that fee’s amount. A candidate who needs to reschedule must contact PSI two days before the scheduled examination date or forfeit the scheduling fee. CONTENT (L&I Plumber Examination page): “The Journey Level and Residential Specialty exams are closed book. Tables 702.1, 610.3, 610.4, and 610.10 are provided with the exam. Table 703.2 is not provided.” Those exams have three parts: technical and general trade knowledge (“100 questions on plumbing code taken from Chapters 1 through 10, 15, 16, and 17 of the UPC and amendments”); code application knowledge for waste and vents (a waste and vent sizing exercise from Chapter 7); and code application for water piping (a water pipe sizing exercise from Chapter 6). L&I states that “Washington state plumber examinations are based on the 2015 Uniform Plumbing Code (UPC) and include amendments as adopted by the Washington State Building Code Council.” By statute the examination determines whether the applicant has general knowledge of the trade and is “familiar with the applicable plumbing codes and the administrative rules of the department pertaining to plumbing and plumbers” (RCW 18.106.050(1)), and “The director may not limit the number of times that a person may take the examination” (18.106.050(4)). RETESTING – TWO OFFICIAL SOURCES DIFFER, both recorded: L&I’s examination page says a candidate who fails must “submit a new application and application fee of $202.10” and “wait 2 weeks (14 calendar days) from your last examination before you will be able to schedule another date with PSI”; WAC 296-400A-121(8) still says an applicant who fails “will be required to wait at least until the next scheduled examination date and location and work under the direct supervision of a certified plumber while holding an active trainee card, until they have passed the exam and their certificate of competency has been issued” and that “Examinations are held the first Thursday of every month, unless that date falls on a holiday.” After passing, the certificate fee must be paid “within ninety days of notification of passing the written examination. Failure to pay within ninety days will require reexamination” (WAC 296-400A-020(1)(h)). “Failure to reschedule or appear on the scheduled exam date will result in forfeiture of the examination fee” (WAC 296-400A-121(9)).
Renewal & continuing education
Certificates of competency: every three years, on the birthday. “The certificate shall bear the date of issuance, and be renewed every three years, upon application, on or before the birthdate of the holder” (RCW 18.106.070(1)(a)); “Plumber certificates are renewed every three years,” and “The individual may not apply for renewal more than ninety days prior to the expiration date” (WAC 296-400A-023(1)). The first certificate runs longer or shorter depending on the birthday: L&I says it is good for “A minimum of 25 months up to a maximum of 37 months for journey level, residential, residential service, backflow, or domestic pump or pump and irrigation plumbers,” and “Your initial fees are the same regardless of the length of time, they are not pro-rated.” LATE: renewing after the renewal date costs a doubled fee, and “If the person does not renew the certificate within ninety days of the renewal date, he or she must retake the examination and pay the examination fee” (RCW 18.106.070(1)(a); WAC 296-400A-023(2)-(3)). L&I: “90 calendar days after your certification has expired – If you haven’t paid your renewal fee and/or you haven’t completed your continuing education requirements, you must retest to reinstate your certification.” Online renewal is unavailable when continuing education is incomplete, when there are outstanding unpaid plumbing infractions, or when the certificate is suspended. “An individual may renew a suspended plumbing certificate” but it stays suspended for the suspension period, and “An individual may not renew a revoked plumbing certificate” (WAC 296-400A-023(7)-(8)). The department may deny renewal to an applicant who owes outstanding penalties for a final judgment (RCW 18.106.100(3)). Trainee certificates: annually – “Your plumber trainee certificate is good for 12 months from the date your application is approved” (L&I); a trainee who has not completed continuing education can renew but the card is placed in inactive status, and plumbing work experience obtained while expired or inactive is not credited (WAC 296-400A-120(2)(e)-(f)). Medical gas endorsement: “Medical gas endorsement is renewed every three years,” with affidavits of continuity of brazing every six months and an affidavit of review of the current medical gas code; expired ninety-one days or more requires the medical gas examination (WAC 296-400A-022). Plumbing contractor license: expires “twenty-four calendar months following the day of its issuance” (RCW 18.106.400(1)); L&I must send a renewal notice no more than forty-five days before it expires (WAC 296-400A-011(2)). Journey level, residential specialty and residential service plumbers: 24 hours per three-year certification period. RCW 18.106.070(1)(a) conditions renewal on the applicant having, “during the past three years,” “completed twenty-four hours of continuing education approved by the department with the advice of the advisory board, including four hours related to electrical safety.” WAC 296-400A-028(1)(a) sets the mix: “a minimum of twelve hours of plumbing code and a minimum of four hours of electrical trade related classes from the currently adopted Washington state plumbing and electrical codes. The remaining eight hours may be plumbing or electrical trade related classes.” L&I states the same as “A minimum of 12 hours of Uniform Plumbing Code (Code), PLUS A minimum of 4 hours of Industry-Related Electrical (IRE). The remaining 8 hours can be in any Code, IRE, or Industry-Related Plumbing (IRP) area,” effective July 1, 2021. BEHAVIORAL HEALTH CREDIT – Laws of 2026, ch. 14 (Substitute House Bill 2492), EFFECTIVE JUNE 11, 2026: “an applicant may count up to four completed hours in behavioral health and wellness training approved by the department towards the total number of required hours,” and the training must include at least two hours of instruction covering destigmatizing behavioral health and supporting wellness, recognizing signs of distress, suicide prevention, substance use disorder awareness and prevention, and providing peer support and connecting to resources (RCW 18.106.070(1)(b)). Domestic pump and pump and irrigation specialty plumbers: 24 hours per three-year period, “with a minimum of twelve of the required twenty-four hours of continuing education in plumbing” (RCW 18.106.070(1)(a); WAC 296-400A-028(1)(b)); L&I’s Continuing Education page states the same plumbing floor – “A minimum of 12 hours of plumbing and up to 12 hours of electrical courses (24 hours total)” – and adds that the electrical program separately requires 24 hours and that combination classes count toward both. TWO OFFICIAL SOURCES DIFFER on the pump split, both recorded: the renewal tables on L&I’s Get or Renew Your Certification page (“These 24 hours must consist of a minimum of 12 hours of electrical and 12 hours of plumbing (Code, IRP).”) and Combination Plumber & Electrician page (“These 24 hours must consist of a minimum of 12 hours of electrical and 12 hours of plumbing (code or IRP).”) also set a 12-hour ELECTRICAL minimum, which the statute, WAC 296-400A-028(1)(b) and the Continuing Education page do not. Plumber trainees: “at least eight hours per year,” and “Trainees will be required during a two-year period to complete at least eight hours of plumbing code and at least four hours of electrical trade related classes,” the remaining four in either category (WAC 296-400A-028(1)(c)); apprentices registered in an approved program and attending approved classroom training are deemed to meet the trainee requirement (WAC 296-400A-120(2)(h)). Backflow specialty plumbers: none – “Continuing education requirements do not apply to backflow specialty plumbers under chapter 18.106 RCW and this chapter” (WAC 296-400A-028(3)); renewal instead requires a current Department of Health BAT certification. Medical gas installers: affidavits of continuity of brazing rather than hours (L&I; WAC 296-400A-022). Credit rules: no credit is granted for any course not approved by the department; “An individual will not be given credit for the same approved continuing education course taken more than once in their renewal cycle” (WAC 296-400A-028(2)); “Any portion of a year of a prior plumber certification period is equal to one year for the purposes of the required continuing education” (-028(1)(d)); course providers report attendance rosters to L&I within 30 days, so the plumber does not submit certificates. Courses are offered online, by correspondence, or in person.
How to apply
Applications are handled by Washington State Department of Labor & Industries (L&I), Plumber Certification Program. Start at the official application page .