What Is a Washington 06B Restricted Master Electrician?

A Washington specialty master electrician is an experienced certified electrician who has completed the additional state requirements for master-level certification.

The master may continue to work with the tools of the trade inside the applicable specialty. The master may also be assigned to an electrical contractor and take responsibility for helping ensure the company's electrical work follows Washington laws and rules.

This distinction is especially important in 06B because the specialty contains several precise voltage, phase, amperage, occupancy, equipment-location, and wiring-method limits.

You Must Hold the 06B Electrician Certificate for Two Years

Washington does not provide a direct jump from trainee status to the specialty master examination.

You must first become a certified 06B HVAC/Refrigeration Restricted Electrician and then hold that specialty electrician certificate for at least two years before qualifying for the master examination.

The Three Numbers Every 06B Master Should Know

The defining restriction for 06B is based on the primary electrical power connection to the HVAC/refrigeration system.

Residential HVAC/R Controls

06B may install, repair, replace, and maintain qualifying HVAC/refrigeration telecommunications and Class 2 low-voltage control wiring and components in residential occupancies.

Examples can include:

• Thermostat wiring.
• Class 2 control circuits.
• HVAC control boards.
• Temperature sensors.
• Pressure sensors.
• Refrigeration controls.
• HVAC/R telecommunications.
• Other qualifying system-control components.

The work still needs to be part of the HVAC or refrigeration system. A low-voltage wire does not become 06B work simply because someone ran it through the same ceiling as the air-conditioning controls.

Nonresidential Low-Voltage Work Has a Three-Story Limit

06B may also install, repair, replace, or maintain qualifying HVAC/R telecommunications and Class 2 low-voltage control wiring in nonresidential occupancies.

However, the occupancy may have no more than three stories on or above grade.

This is one of the important differences between 06A and 06B. A project can involve identical thermostat or control wiring, yet the building itself can determine whether 06B may legally perform the work.

Line-Voltage Components Inside HVAC/R Equipment

06B may install, repair, replace, and maintain qualifying line-voltage components located within HVAC/refrigeration equipment.

Examples may include:

• Internal contactors.
• Relays.
• Control components.
• Motor-related components.
• Factory-authorized accessories.
• Internally mounted outlets authorized by the equipment manufacturer.
• Product-illumination luminaires located within and powered from refrigeration equipment.

Product illumination can include lighting inside equipment such as reach-in beverage coolers, frozen-food cases, and produce cases.

The phrase within HVAC/refrigeration equipment matters. Similar equipment mounted externally may fall outside the specialty.

Internal Disconnect and Controller Components

06B may repair, replace, or maintain internal components of the HVAC/refrigeration equipment disconnecting means or controller.

The disconnect or controller cannot be located within a motor control center or panelboard.

This allows specialty electricians to service parts of qualifying HVAC/R equipment without giving them general authority to perform electrical work in panelboards or motor control centers.

The Six-Foot Flexible Supply Whip Rule

06B may repair, replace, or maintain line-voltage flexible supply whips that are not more than six feet long.

The work cannot modify the characteristics of the branch-circuit or feeder load being supplied by the whip, except for a permitted reduction in the HVAC unit's rated maximum overcurrent protection size.

Washington does not require the replacement whip to use exactly the same raceway method. An approved metallic whip can be replaced by an approved nonmetallic method when otherwise permitted.

Short Raceway Sections for Low-Voltage Protection

06B may install, repair, replace, and maintain short sections of raceway used to provide physical protection for low-voltage cable.

The short raceway cannot mechanically interconnect two devices, junction boxes, equipment pieces, or other components.

This is a protective-raceway allowance. It is not permission to install a normal conduit system throughout the building.

A sleeve that protects cable from physical damage and a raceway system connecting several electrical boxes may both look like pipe, but Washington treats them very differently.

External Line-Voltage Disconnects Are Generally Outside 06B

The 06B specialty generally may not install line-voltage controllers or disconnect switches external to HVAC/refrigeration equipment.

Washington provides a narrow exception when qualifying HVAC/R equipment is being replaced.

Under that exception, 06B may remove and replace a disconnecting-means enclosure mounted on the surface of the HVAC/R equipment when the replacement is like-in-kind and rated no more than 20 amperes and 120 volts.

The existing wiring method must be used.

While performing this specific work, the specialty may install up to 10 feet of raceway to provide physical protection for nonmetallic cable. That raceway may not terminate in a panelboard.

Integrated Building Controls Have Limits

06B may work on qualifying HVAC/refrigeration controls.

It does not provide general authority over integrated building-control systems that extend beyond HVAC or refrigeration.

For example, one building automation platform might connect HVAC, lighting, security, elevators, and energy systems. The HVAC/R control portion may fit the specialty while the entire building automation system does not.

Whenever a question says "building controls," ask what the controls actually operate.

Stand-Alone Line-Voltage Equipment Is Generally Outside 06B

06B does not generally include stand-alone line-voltage equipment or components such as:

• Heat cable.
• Wall heaters.
• Radiant-panel heaters.
• Baseboard heaters.
• Stand-alone contactors.
• Motor starters.
• Similar independent electrical equipment.

Washington provides exceptions when equipment is exclusively controlled by the HVAC/R system and requires an additional external connection to a mechanical system as an integral part of operation, or when the HVAC/refrigeration mechanical system is physically contained within the equipment.

The question is not simply whether the equipment produces heat or cooling. The mechanical relationship to the HVAC/R system matters.

General Building Lighting Is Outside the Specialty

General luminaires used to light a building or structure are outside normal 06B authority even when the fixture is mechanically associated with HVAC/R equipment.

Examples include:

• A troffer luminaire that also serves as a return-air device.
• Personnel lighting inside a walk-in cooler or freezer.
• General room illumination mechanically attached to HVAC-related equipment.

Product illumination located inside and powered from qualifying refrigeration equipment is different and may fall within 06B.

General Premises Wiring Is Outside 06B

The restricted HVAC/R specialty is not a general premises-wiring classification.

Work generally outside 06B includes:

• General electrical services.
• General feeders.
• General line-voltage branch circuits.
• General raceway and conduit systems.
• External panelboards.
• External switchboards.
• External motor control centers.
• General building lighting.
• Integrated building controls outside the HVAC/R system.

Classified-Location Work Is Restricted

06B does not provide general authority to perform electrical work governed by NEC classified-location articles outside qualifying HVAC/refrigeration equipment.

The current master examination still contains approximately one Hazardous Locations question.

That means a master candidate should know enough to identify a classified-location issue and understand when the work falls outside the specialty.

The NEC tells you how classified work must be installed. Washington licensing rules tell you whether your specialty may install it. Those are two different questions.

06B vs. 06A HVAC/Refrigeration

The easiest way to understand 06B is to compare it with the broader 06A HVAC/Refrigeration specialty.

06A is not generally limited by voltage, phase, or amperage.

06B cannot perform work when the HVAC/R system's primary electrical power connection exceeds:

• 250 volts.
• Single phase.
• 120 amperes.

06A also has broader low-voltage authority in certain nonresidential occupancies.

The Underlying 06B Electrician Path

Before becoming a master, you must first become a certified 06B electrician.

The underlying 06B specialty is one of Washington's 2,000-hour specialty classifications.

After you obtain the full 06B electrician certificate, the two-year specialty-master clock begins.

What Can a 06B Master Electrician Do?

A properly certified 06B Master Electrician may personally perform qualifying HVAC/R Restricted electrical work.

The master may also supervise electrical trainees working inside the specialty and may serve as a contractor's designated specialty master.

The role can include:

• Performing qualifying 06B electrical installations.
• Working on HVAC/R Class 2 control circuits.
• Working on qualifying telecommunications associated with HVAC/R.
• Servicing line-voltage components within HVAC/R equipment.
• Servicing qualifying internal disconnect and controller components.
• Repairing or replacing qualifying six-foot supply whips.
• Supervising trainees.
• Reviewing specialty-scope compliance.
• Monitoring electrician certifications.
• Monitoring permits and inspections.
• Serving as a contractor's designated specialty master.

Assignment to an Electrical Contractor

Receiving your master certificate and becoming assigned to a contractor are separate steps.

When properly assigned, a specialty master serves in the administrator role for an electrical contractor and helps ensure the contractor's electrical work complies with state law and remains inside the authorized specialty.

The current Washington fee for assignment or unassignment of a master electrician or administrator designation is $53.00.

The Current 06B Master Electrician Exam at a Glance

Current 06B Master Electrician Exam Blueprint

The number of questions in each individual knowledge area is approximate, but the blueprint gives you a very useful study map.

General Trade Knowledge and Theory Is About Six Questions

The current master technical outline gives approximately six questions to General Trade Knowledge and Theory.

Review:

• Voltage.
• Current.
• Resistance.
• Power.
• Ohm's law.
• Series and parallel circuits.
• Basic AC theory.
• Electrical measurements.
• Troubleshooting concepts.
• Equipment ratings.
• Trade calculations.

Six theory questions out of 34 is significant. The faster you can solve these without opening a reference book, the more time you have for difficult code lookups.

Wiring Methods Are About Five Questions

NEC 300 through 398 contributes approximately five questions.

Review:

• Cable installation.
• Raceways and fittings.
• Boxes.
• Outdoor wiring.
• Wet and damp locations.
• Equipment connections.
• Support and securing.
• Protection from physical damage.

Keep technical permission and licensing permission separate. The NEC can describe a perfectly legal raceway installation even when Washington's 06B license does not authorize you to install that general raceway system.

Motors and HVAC Equipment Are About Five Questions

NEC 430 through 450 contributes approximately five questions to the current master technical section.

Study:

• Motor full-load current.
• Motor conductors.
• Motor overload protection.
• Short-circuit and ground-fault protection.
• Controllers.
• Disconnecting means.
• Hermetic refrigerant motor-compressors.
• Motor tables.
• HVAC equipment.
• Transformer concepts.
• Equipment nameplates.

This is an HVAC/R master exam, so motor and compressor rules deserve a large part of your study schedule.

Overcurrent Protection Is About Four Questions

NEC Article 240 contributes approximately four questions.

Study conductor protection, equipment protection, standard ratings, permitted overcurrent devices, and the interaction between general overcurrent requirements and HVAC/motor-specific rules.

Do not confuse motor overload protection with branch-circuit short-circuit and ground-fault protection. They are different protections with different sizing rules.

Grounding and Bonding Is About Four Questions

NEC Article 250 contributes approximately four questions.

Review:

• Equipment grounding conductors.
• Bonding.
• Effective fault-current paths.
• Grounding electrodes where applicable.
• Grounding electrode conductors.
• Equipment grounding around HVAC/R systems.
• Metal raceway bonding.

Picture the actual equipment and the path fault current needs to take. That usually makes grounding questions easier than memorizing a stack of unrelated definitions.

General Requirements Are About Three Questions

NEC 100 through 110 contributes approximately three questions to the master exam.

Definitions, working space, equipment installation, listing, labeling, interrupting ratings, and general electrical-installation requirements can all affect HVAC/R equipment.

These articles are easy to underestimate because they appear near the front of the code book. The exam does not underestimate them.

Special Conditions Are About Three Questions

NEC 705 through 780 contributes approximately three questions.

The special-condition articles cover electrical systems and circumstances that can interact with HVAC/R equipment and control systems.

Learn the organization of these articles so you can locate the relevant rule without spending half the exam performing an archaeological dig through the NEC.

Electrical Equipment Is About Two Questions

NEC 400-427 and 455-480 contributes approximately two questions.

This area includes equipment and wiring topics that can interact with HVAC/R systems, flexible connections, transformers, heating equipment, and other electrical components.

Pay attention to where the component is located. The same kind of device may fall inside or outside 06B depending on whether it is part of the qualifying HVAC/R equipment.

Hazardous Locations Are About One Question

NEC 500 through 516 contributes approximately one question.

06B does not provide general authority for classified-location electrical work outside qualifying HVAC/R equipment.

You should still understand the basic NEC classifications and know where to locate the rules because the master exam tests technical knowledge as well as licensing scope.

The Washington Codes Section Has 20 Questions

The 06B Master Electrician examination contains approximately 20 Washington Laws & Rules questions.

This is a larger Washington section than the 17-question section used for the 06B electrician and administrator examinations.

Study:

• Chapter 19.28 RCW.
• Chapter 296-46B WAC.
• WAC 296-46B-920 specialty scope.
• Master electrician eligibility.
• Specialty electrician certification.
• Trainee supervision.
• Electrical contractor licensing.
• Master assignment.
• Permits.
• Inspections.
• Renewal.
• Continuing education.

At the master level, Washington expects you to understand both the technical installation and the rules governing who may perform the work.

The Current Exam Is Open Book

The current Washington electrical examination is open book.

The current core references are:

• 2020 National Electrical Code.
• Current Chapter 19.28 RCW.
• Current Chapter 296-46B WAC.

Original copyrighted references may contain highlighting, underlining, and permanent index tabs prepared before entering the examination area.

Handwritten notes, Post-It notes, sticky notes, removable notes, and repositionable tabs are prohibited under the current rules.

Printed copies of Washington RCW and WAC materials may be used when prepared according to the testing provider's binder requirements.

A silent, nonprinting, nonprogrammable calculator is permitted.

Exam NEC vs. Washington Field NEC

The current PSI licensing bulletin still identifies the 2020 National Electrical Code as the examination reference.

Washington field installations currently use the 2023 NEC.

Washington has scheduled the 2026 NEC to replace the 2023 edition for field installations on December 31, 2026.

Always verify the current PSI bulletin close to your actual examination date.

A Practical Open-Book Master Exam Strategy

1. Memorize the 06B limits. 250 volts, single phase, 120 amps.
2. Know the three-story nonresidential low-voltage limit.
3. Know the six-foot supply-whip rule.
4. Learn the external-disconnect restriction and replacement exception.
5. Understand the difference between 06A and 06B.
6. Practice General Trade Knowledge & Theory.
7. Study NEC 430-450 Motors and HVAC Equipment.
8. Study NEC 300-398 Wiring Methods.
9. Study NEC 240 Overcurrent Protection.
10. Study NEC 250 Grounding & Bonding.
11. Review Special Conditions.
12. Study Washington master and contractor rules.
13. Take 34-question technical practice exams in two hours.
14. Take 20-question Washington-law practice exams in one hour.

Apply Through Labor & Industries Before PSI

06B Master Electrician candidates must first apply through Washington Labor & Industries.

L&I verifies that the applicant has held the matching 06B specialty electrician certificate for at least two years.

After L&I approves the application, the candidate receives the eligibility information needed to schedule the examination through PSI.

Approved candidates currently have one year from the approval date to successfully complete all required examination sections.

For help organizing the licensing application, review 1 Exam Prep application services.

Retesting Rules

If you fail a required examination section, current PSI rules require a waiting period before another attempt.

The normal waiting period is at least 14 days.

After a third failed attempt, you must wait three months from the most recent failure date before each future attempt.

All required sections must be completed within the one-year approval period.

If that eligibility period expires before you complete the exam, you must reapply through Labor & Industries.

Current 06B Master Electrician Fees

The current master electrician renewal fee completed in person, by mail, or by fax is $202.20.

Fees can change, so verify the amount in effect when you apply, test, assign, or renew.

For the exact exam-reference package built around this specialty, review the Washington B-HVAC/R Restricted Master Electrician Book Package.

For books, testing expenses, and licensing costs, review 1 Exam Prep financing options.

The Master Certificate Replaces Your 06B Electrician Certificate

When Washington issues your 06B HVAC/R Restricted Master Electrician certificate, the master certificate replaces your existing 06B specialty electrician certificate.

You do not carry both an electrician certificate and a master electrician certificate in the same specialty classification.

You may continue performing hands-on specialty electrical work while also carrying the added supervisory responsibilities of a master electrician.

Renewal and Continuing Education

Washington master electrician certificates normally renew every three years.

The first certificate period depends on your birthdate and the date the credential is issued. Washington states that the initial master certificate is generally valid for at least 25 months and no more than 36 months.

A normal three-year certification period requires 24 hours of approved continuing education.

• At least 8 hours must cover changes in the currently adopted electrical code.
• At least 4 hours must cover current Chapter 19.28 RCW and/or related WAC requirements.
• The remaining required hours may cover approved industry-related subjects.

If your master certificate is more than 90 days past its expiration date, Washington requires you to reapply and pass the appropriate master examination to restore certification.

If the master is assigned to an electrical contractor, certificate expiration can also affect that contractor assignment.

A Practical 06B Master Study Plan

1. Start with WAC 296-46B-920. Learn every 06B permission and restriction.
2. Memorize 250 volts, single phase, 120 amps.
3. Memorize the three-story nonresidential limit.
4. Learn the six-foot flexible-whip rule.
5. Learn the 20-amp, 120-volt disconnect-replacement exception.
6. Study General Trade Knowledge & Theory.
7. Study NEC 430-450 Motors and HVAC Equipment.
8. Study NEC 300-398 Wiring Methods.
9. Study NEC 240 Overcurrent Protection.
10. Study NEC 250 Grounding & Bonding.
11. Review General Requirements.
12. Review Special Conditions and Hazardous Locations.
13. Study contractor, master, permit, and inspection rules.
14. Practice 34 technical questions in two hours.
15. Practice 20 Washington-law questions in one hour.

Use the Washington B-HVAC/R Restricted Master Electrician collection from 1 Exam Prep to organize your preparation around the current examination.

Study Like an HVAC/R Restricted Master Electrician

A useful master-level study method is to picture an actual HVAC/R project and work through three sets of questions.

First, check the specialty scope. What is the system's primary power connection? Is it 250 volts or less? Is it single phase? Is it 120 amps or less? Is the building residential or nonresidential? If nonresidential low-voltage control wiring is involved, how many stories does the building have?

Second, inspect the electrical installation. Which wiring method applies? What motor or compressor rules control the circuit? What overcurrent protection is required? How is the equipment grounded and bonded? Where is the disconnect? Is the component inside the HVAC/R equipment or external to it?

Third, think like the master. Is the electrical contractor licensed for the correct specialty? Are electricians properly certified? Are trainees properly supervised? Does the proposed work cross into a service, feeder, branch circuit, panelboard, raceway system, or other work outside 06B?

This three-part approach, scope, technical code, and contractor compliance, turns master-exam preparation into the same decision-making process used on real jobs.

Frequently Asked Questions

Conclusion

The Washington 06B HVAC/Refrigeration Restricted Master Electrician certificate is the advanced credential for electricians who have already built experience inside the state's restricted HVAC/R specialty and want to move into master-level responsibility.

The pathway begins with the 06B electrician certificate. Washington requires a specialty master applicant to hold that matching certificate for at least two years before qualifying for the master examination. That requirement makes the master credential an advancement from certified specialty electrician rather than a shortcut around the electrician pathway.

The three numbers that define the specialty remain 250 volts, single phase, and 120 amps. If the HVAC/R system's primary electrical power connection exceeds one of those limits, the work is outside 06B regardless of whether the person holds an electrician or master electrician certificate.

The master credential does not remove the restriction. It adds supervisory and contractor-level responsibility while preserving the same specialty boundary.

Inside that boundary, 06B covers substantial HVAC/R electrical work. The specialty may install, repair, replace, and maintain qualifying HVAC/R telecommunications and Class 2 controls in residential occupancies. It may perform qualifying low-voltage HVAC/R work in nonresidential occupancies with no more than three stories on or above grade.

06B may also install, repair, replace, and maintain line-voltage components located within qualifying HVAC/refrigeration equipment. This can include internal controls, contactors, relays, approved accessories, internally mounted outlets, and product-illumination equipment within refrigeration systems.

The specialty may repair, replace, or maintain internal components of qualifying equipment disconnects and controllers when those devices are not located inside a motor control center or panelboard.

The six-foot flexible-whip rule is another major specialty detail. A qualifying line-voltage flexible supply whip not more than six feet long may be repaired, replaced, or maintained as long as the characteristics of the supplying circuit are not improperly modified.

Short sections of raceway may also be used for physical protection of low-voltage cable. Those sections cannot become general raceway systems that mechanically interconnect electrical boxes, devices, or equipment.

The specialty has clear exclusions. General electrical services, feeders, branch circuits, external panelboards, switchboards, motor control centers, ordinary building lighting, and general raceway systems are outside normal 06B authority.

External line-voltage disconnects and controllers are also generally outside the specialty. Washington does provide a narrow replacement exception for certain equipment-mounted disconnecting-means enclosures when qualifying HVAC/R equipment is replaced. The replacement is limited to a like-in-kind enclosure rated no more than 20 amps and 120 volts, with additional conditions applying to the wiring method and protective raceway.

The current 06B Master Electrician examination contains approximately 34 NEC and Theory questions plus 20 Washington Laws and Rules questions. Candidates receive two hours for the technical section and one hour for Washington Codes. That gives a total of 54 published scored questions across three section-hours.

General Trade Knowledge and Theory represents approximately six technical questions. Wiring Methods and Motors, HVAC, Generators and Transformers contribute about five questions each. Overcurrent Protection and Grounding and Bonding contribute about four questions each.

General Requirements and Special Conditions also receive meaningful attention, along with Electrical Equipment and Hazardous Locations.

The Washington section contains 20 questions, which means licensing law deserves serious preparation. Master candidates should understand specialty scope, master eligibility, contractor licensing, certification, supervision, assignment, permits, inspections, renewal, and continuing education.

The current examination remains open book. PSI currently identifies the 2020 National Electrical Code, current Chapter 19.28 RCW, and current Chapter 296-46B WAC as the primary references. Candidates may prepare original copyrighted books with permitted highlighting, underlining, and permanent tabs, but removable notes and repositionable tabs are prohibited.

Washington's field-code timeline is currently different from the licensing-exam reference. Field installations use the 2023 NEC, while the current PSI exam bulletin continues to identify the 2020 NEC. Washington has scheduled the 2026 NEC to replace the 2023 field edition on December 31, 2026, so candidates should verify the PSI bulletin near their actual exam date.

Master applicants begin with Labor & Industries. L&I verifies the required two years holding the 06B electrician certificate before providing eligibility to schedule through PSI.

The current three-hour PSI master examination fee is $65. Washington currently charges $204.60 for the master electrician exam application, including the original certificate and application processing fee.

Once issued, the master certificate replaces the existing 06B electrician certificate. The master credential continues to authorize qualifying hands-on specialty work while adding master-level supervisory authority.

Master electrician certificates normally renew every three years. Current online renewal is $175.70, while renewal by mail, fax, or in person is $202.20. Assignment or unassignment currently costs $53.

A normal three-year certification period requires 24 hours of approved continuing education. At least eight hours must cover changes in the electrical code, at least four hours must cover Washington electrical law and rules, and the remaining hours may cover other approved subjects.

The best preparation combines specialty scope with technical code knowledge. Begin every problem by checking whether it fits 06B. Look at voltage, phase, amperage, occupancy, building height, equipment location, and the type of electrical work being proposed.

Then solve the technical problem. Determine which motor, overcurrent, grounding, wiring-method, or equipment rule applies. Finally, think like a master electrician and check whether the contractor, electrician, trainee, permit, and inspection requirements are correct.

When those three layers become automatic, you are doing more than preparing to answer 54 exam questions. You are practicing the judgment expected from a Washington 06B HVAC/R Restricted Master Electrician.

Key Takeaways

• You must hold the Washington 06B HVAC/Refrigeration Restricted electrician certificate for at least two years before qualifying for the specialty master exam.
• 06B is limited to qualifying HVAC/R systems whose primary electrical power connection does not exceed 250 volts, single phase, or 120 amps.
• The current master exam contains 34 NEC/Theory questions in two hours plus 20 Washington Codes questions in one hour, for 54 scored questions.
• The current exam is open book, requires 70 percent to pass, and currently uses the 2020 NEC plus current RCW 19.28 and WAC 296-46B.
• Focus heavily on specialty scope, theory, motors and HVAC equipment, wiring methods, overcurrent protection, grounding and bonding, and Washington master/contractor rules.

Plain-Language Summary

The Washington 06B HVAC/Refrigeration Restricted Master Electrician certificate is for experienced 06B electricians who want to move to the master level.

You cannot start with the master certificate. First, you must become a certified Washington 06B HVAC/Refrigeration Restricted Electrician. You must then hold that specialty electrician certificate for at least two years before becoming eligible for the master examination.

A 06B master can continue doing hands-on electrical work within the specialty. The master can also serve as the designated specialty master for an electrical contractor when properly assigned.

The most important limits are 250 volts, single phase, and 120 amps. The primary electrical power connection to the HVAC/R system cannot exceed any of those limits.

The specialty can perform qualifying low-voltage HVAC/R control and telecommunications work in residential buildings. It can also perform qualifying low-voltage HVAC/R work in nonresidential occupancies with no more than three stories on or above grade.

06B can install, repair, replace, and maintain qualifying line-voltage components located inside HVAC or refrigeration equipment. Examples can include internal contactors, relays, controls, approved accessories, and certain product-illumination equipment inside refrigeration systems.

The specialty can also repair and replace internal components of qualifying HVAC/R equipment disconnects and controllers as long as those devices are not located inside a motor control center or panelboard.

Another important rule involves flexible supply whips. 06B can repair, replace, or maintain qualifying line-voltage flexible supply whips up to six feet long when the supplying branch circuit or feeder is not improperly changed.

Short sections of raceway can be installed to physically protect low-voltage cables. Those short sections cannot be used to build a general raceway system connecting boxes and equipment.

External line-voltage disconnects are generally outside 06B. Washington provides a narrow exception when qualifying HVAC/R equipment is being replaced. Under that exception, certain like-in-kind disconnect enclosures mounted on the equipment can be replaced when they are rated no more than 20 amps and 120 volts and the other conditions in the rule are satisfied.

The specialty does not provide general authority to install services, feeders, ordinary branch circuits, panelboards, switchboards, motor control centers, general lighting, or general raceway systems.

The current master examination contains approximately 34 NEC and Theory questions. Candidates receive two hours for this section. Washington Codes contains approximately 20 questions and allows one hour. That creates a total of 54 published scored questions.

General Trade Knowledge and Theory contributes approximately six questions. Wiring Methods contributes about five. Motors, HVAC, Generators and Transformers contributes about five.

Overcurrent Protection and Grounding and Bonding contribute about four questions each. General Requirements contributes about three, and Special Conditions contributes about three. Electrical Equipment and Hazardous Locations make up the remaining technical areas.

The Washington Codes section tests state laws and rules involving specialty scope, master eligibility, contractor responsibilities, electrician certification, trainee supervision, master assignment, permits, inspections, renewal, and continuing education.

The current examination is open book. PSI currently identifies the 2020 National Electrical Code together with current RCW Chapter 19.28 and WAC Chapter 296-46B as the main references.

The passing score is currently 70 percent on each required section.

Master candidates first apply through Washington Labor & Industries. L&I verifies that the candidate has held the matching 06B specialty electrician certificate for at least two years. After approval, the candidate schedules the examination through PSI.

The current three-hour master examination fee is $65. Washington currently charges $204.60 for the master electrician application including the original certificate and processing fee.

When the master certificate is issued, it replaces the existing 06B electrician certificate in that classification.

Master certificates normally renew every three years. Current online renewal is $175.70. Renewal by mail, fax, or in person is $202.20. Assignment or unassignment currently costs $53.

A normal three-year renewal period requires 24 hours of approved continuing education. At least eight hours must cover electrical-code changes and at least four hours must cover Washington RCW/WAC requirements.

For efficient preparation, begin with the specialty limits. Memorize 250 volts, single phase, 120 amps, the three-story nonresidential control limit, the six-foot whip rule, and the external-disconnect restriction.

Then focus on electrical theory, motors and HVAC equipment, wiring methods, overcurrent protection, grounding and bonding, general requirements, and Washington electrical law.

Practice with the same code books you plan to use at the testing center. Open book is useful, but only when you can find the answer before the exam clock decides to become the most interesting thing in the room.

Use the Washington B-HVAC/R Restricted Master Electrician collection from 1 Exam Prep to organize your preparation around the current 06B master examination.