What It Takes to Become a Licensed Plumber

The legendary actor Spencer Tracy once said: “Acting is not an important job in the scheme of things. Plumbing is.”

If you’ve ever had a plumbing emergency, you know what he means. You need someone who knows how to fix it right! And that plumber is made, not born.

The plumbing profession is complex, with many specialties and regulations. All plumbers in Washington  have to be certified by the state and complete specific educational requirements at all levels, from trainee to specialist.

Right now, the state Department of Labor and Industries oversees the certification of more than 6,000 plumbers and 3,000 plumber trainees.

The Entry Level

To start a career in plumbing, you have to be 16 years old, and begin as a trainee. Trainees must register with the state and work under the direct supervision of a certified plumber. The law specifies how this supervision works, with no more than two trainees per supervisor.

Further, supervision must be a minimum of 75 percent of the time spent on each job. In addition, trainees must take 8 hours of  plumbing courses at an approved school per year. Trainees can renew their certificates each year. 

Moving Up

To move up the plumbing ladder takes more classroom work and more experience on-the-job.

To become a journey level or specialty plumber, trainees must complete 8,000 hours over at least 4 years, working as a trainee with a certified plumber. Half of those hours have to be working in a commercial or industrial setting. In addition, specific plumbing classroom education at an approved school must be completed.

The state also takes into account similar military training.

A journey level plumber is qualified to work in all areas of plumbing. Plumbing specialties include pumps and irrigation, back flow, and domestic wells. Each speciality has its own qualifications and exams.

Consumer Education and Safety

The State Department of Labor and Industries is also concerned with consumer education and consumer safety. It has an ad campaign to encourage homeowners to hire certified plumbers and ask to see their plumber certification card.

The department  has compliance inspectors in each country, and a web page for consumers to report problems.


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