Process and Requirements to become a Plumbing Contractor In Washington State

If you're aiming to become a licensed plumber in Washington State, it's essential to understand the certification requirements and process overseen by the Washington State Department of Labor & Industries (L&I). This guide provides a comprehensive overview to help you navigate the steps toward licensure.

Step 1: Begin as a Plumber Trainee

To start your plumbing career in Washington, you must first obtain a plumber trainee certificate. This allows you to gain hands-on experience under the supervision of a certified plumber.

Requirements:

  • Be at least 16 years old.
  • Apply for a plumber trainee certificate through L&I.
  • Work under the direct supervision of a certified plumber.
  • Complete 8 hours of approved continuing education annually to renew your trainee certificate.

Step 2: Accumulate Required Work Experience

As a trainee, you'll need to log a specific number of supervised work hours, depending on the certification you aim to achieve:

  • Journey Level (PL01): 8,000 hours (approximately 4 years), with at least 4,000 hours in commercial or industrial plumbing.
  • Residential Specialty (PL02): 6,000 hours (approximately 3 years) in residential plumbing.
  • Residential Service (PL04): 4,000 hours (approximately 2 years), with the first 2,000 hours under direct supervision.
  • Pump and Irrigation (PL03): 4,000 hours (approximately 2 years) in the specialty, plus electrical certification.
  • Domestic Well (PL03A): 2,000 hours (approximately 1 year) in the specialty, plus electrical certification.
  • Backflow (PL30): Requires an active Backflow Assembly Tester (BAT) certification from the Washington State Department of Health.

Step 3: Apply for Certification and Pass the Exam

Once you've met the experience requirements, you can apply for the appropriate plumber certification and schedule your exam.

Application Process:

  • Submit the Plumber Certification Application to L&I.
  • Include affidavits of experience documenting your work hours.
  • Pay the examination fee ($189.80 for most certifications).
  • Upon passing the exam, pay the certification fee ($227.90 for journey level, residential, and residential service).

Exam Details:

  • Administered by PSI at various locations across Washington.
  • Covers topics such as plumbing codes, system design, and safety practices.
  • A passing score is typically 70% or higher.

Step 4: Maintain Your Certification

Plumber certifications in Washington must be renewed every three years on your birthday. To renew, you must complete continuing education requirements:

  • Journey Level, Residential, and Residential Service Plumbers: 24 hours of continuing education, including 12 hours of plumbing code and 4 hours of industry-related electrical.
  • Pump and Irrigation, Domestic Well, and Backflow Plumbers: 24 hours of continuing education, with specific requirements based on the specialty.

Additional Considerations

  • Reciprocity: Washington has reciprocal certification with Idaho for journey level plumbers. Out-of-state applicants from other states must provide documentation of equivalent experience or licensure for consideration.
  • Contractor Licensing: If you plan to operate your own plumbing business, you must obtain a plumbing contractor license, which includes additional requirements such as bonding and insurance.

For more detailed information and to access application forms, visit the Washington State Department of Labor & Industries Plumber Certification page.

If you need assistance with insurance or bonding requirements, feel free to reach out for guidance tailored to your plumbing business needs.

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