Blog

The plumbing industry in Washington State provides many opportunities for professional growth. Thanks to new regulatory structures and standards, the job market is growing for certified plumbers.

In the state of Washington, those who are working in the plumbing trade must be adequately certified. The Washington State Plumber Certification Program provides all licenses for plumbing professionals in the state.

What Work Requires a Washington Plumbing License?

Most people are unsure about the types of work that require a plumbing license in Washington state. The plumbing trade includes working on the following types of systems:

• Any structure’s potable water supply or water distribution pipes
• Fixtures and traps related to a building’s water usage
• Water drainage and venting pipes
• Water-related accessories within a building’s property lines
• Medical vacuum systems
• Medical gas systems
• Hot water heater systems

In short, most of these plumbing systems are inside buildings and residences.

Typically, you are not required to have a plumbing certification to install systems outside of structures. 

These systems include external water lines that are connected to municipal mains. A sewer line connection is another example of an external plumbing system. 

The exception to this rule is domestic pump and water irrigation systems. To work on or install these systems, a Washington state plumbing license is necessary.

What Are the Requirements for Washington Plumbing Certifications?

Many people hope to take advantage of the growing job market by becoming a journeyman or specialty plumber in Washington. To reach the journeyman level of certification, most people must begin as a plumber trainee.

There are some exceptions to this. If you are a certified journeyman level plumber in another state, you may be able to secure a similar license in Washington.

For instance, Washington state offers reciprocal certification for journeyman-level plumbers from Idaho. As noted above, those who are new to the trade will begin at the trainee level.

Plumbing Trainees

Those who operate at the trainee level work directly under the supervision of a certified plumber. For the most part, trainees learn their trade through on-site training. 

The requirements for becoming a plumber trainee are:

• Complete a plumber trainee application
• Be at least 16 years of age
• Work under the supervision of a journeyman or specialty plumber
• Obtain the required number of experience hours
• Hold an electrical trainee card for pump or irrigation system work
• Complete eight hours of continuing education annually

Trainees are responsible for logging experience hours by submitting affidavits of experience once each year. When you have met all the requirements, you will become eligible to take the exam for a journeyman-level or specialty plumbing license.

To qualify for the exam, trainees must have at least four years of experience. Alternatively, they can log 8,000 hours. 

All their experience hours must be overseen by a certified journey level or specialty plumber. Half of the logged hours must be spent working on industrial and commercial installations.

Medical Gas Piping Installer

Medical Gas Piping Installers are a specialized type of journey-level plumber. Individuals who hold this certification (MG01) are qualified to install and repair medical gas piping systems.

These systems deliver gasses for medical purposes. Examples of medically relevant gasses include:

• Nitrous oxide
• Oxygen
• High-pressure nitrogen
• Compressed air

This type of certification is also required for those who install and repair medical vacuum systems. 

RocketCert Expert-Level Training

For those who are interested in obtaining a plumbing or contractor’s license in Washington, RocketCert can help. We offer step-by-step guides and industry-leading training options. 

We also provide top-quality exam preparation resources and continuing education. Whether you are applying for the first time or seeking renewal, RocketCert is the answer. 

All our programs are subject to our No Pass, No Pay guarantee. Contact RocketCert today to learn more!