The 1 Package: All-Inclusive Arizona Plumbing Commercial Contractor (C-37) Exam, Licensing & Business Setup Solution

Prepare for the Arizona Plumbing Commercial Contractor C-37 exam while building the licensing and business foundation needed to operate professionally. The 1 Package combines commercial plumbing exam preparation, highlighted and tabbed reference books, contractor application assistance, business formation, EIN filing, and contractor compliance guidance in one coordinated solution.

This all-inclusive Arizona C-37 contractor package is designed for experienced plumbers, pipefitters, plumbing supervisors, hydronic-heating professionals, fire-sprinkler specialists, qualifying parties, estimators, project managers, and business owners pursuing authority to perform qualifying commercial plumbing work in Arizona.

The Arizona C-37 classification covers qualifying commercial plumbing installation, alteration, and repair performed within property lines and outside public easements or rights-of-way, subject to the classification’s authorized scope. The work may include water-supply piping, sanitary drainage, vents, fixtures, appliances, pressure vessels, tanks, gas piping, hydronic systems, fire-sprinkler piping, and connections between structures and approved points of public or private supply or disposal.

Commercial plumbing requires more than installing pipe and fixtures. Contractors must understand water distribution, drainage, venting, indirect waste, backflow prevention, interceptors, traps, fuel gas, hydronic heating, fire sprinklers, excavation, piping materials, testing, equipment connections, estimating, plan reading, and construction safety.

Projects may involve offices, restaurants, medical facilities, schools, hotels, warehouses, industrial buildings, apartment properties, retail spaces, institutional facilities, and commercial tenant improvements. Each project can present different requirements involving occupancy, water demand, drainage loads, fixture quantities, fuel-gas equipment, heating systems, fire protection, accessibility, and coordination with other construction trades.

The included International Plumbing Code, 2018 supports preparation involving water supplies, sanitary drainage, vents, fixtures, traps, interceptors, backflow prevention, indirect waste, storm drainage, piping materials, testing, and plumbing-system installation. The International Fuel Gas Code, 2018 supports preparation involving gas-piping materials, sizing, appliance connections, shutoff valves, regulators, pressure testing, combustion air, and venting.

The International Mechanical Code, 2018 supports study involving boilers, hydronic systems, mechanical equipment, piping, ventilation, equipment access, combustion-related requirements, and system testing. NFPA 13, NFPA 13D, and NFPA 13R support preparation involving sprinkler-system components, water supplies, piping arrangements, installation requirements, residential sprinkler applications, and system coordination.

Mathematics for Plumbers and Pipefitters, 8th Edition supports trade calculations involving fractions, decimals, percentages, geometry, pipe measurements, offsets, elevations, slopes, volumes, and pressure. IPT’s Pipe Trades Handbook provides field-oriented information involving pipe, fittings, flanges, valves, dimensions, weights, formulas, and practical trade data.

Boiler Operator’s Guide, 5th Edition and Modern Hydronic Heating for Residential and Light Commercial Buildings support preparation involving boilers, pumps, controls, heat emitters, piping arrangements, expansion control, air removal, heat loss, system operation, and hydronic troubleshooting. Pipe and excavation safety is reinforced through OSHA 29 CFR Part 1926 and the Arizona 811 Arizona Blue Stake Brochure.

The package includes 1 year of course access, allowing candidates to prepare around active projects, service work, employment, and personal responsibilities. The course supports organized code review, plumbing calculations, reference navigation, commercial-system preparation, and confidence-building study.

Exam Details

The Arizona Registrar of Contractors issues separate commercial, residential, and dual contractor licenses. The C-37 Plumbing classification is the commercial specialty license for qualifying plumbing work performed on commercial buildings, structures, and property.

The qualifying party is the person whose experience, knowledge, and examination qualifications support the contractor license. This individual must satisfy the applicable Arizona requirements and remain associated with the licensed business in the qualifying capacity recognized by the state.

C-37 exam preparation may include drainage, waste and vent systems, indirect waste, water-supply systems, backflow prevention, roof drains, storm drainage, plumbing fixtures, accessibility, specialty plumbing, interceptors, traps, fuel gas, septic and sewer systems, hydronics, fire sprinklers, excavation, and general plumbing knowledge.

Water-supply preparation may include service piping, distribution systems, pressure, velocity, pipe sizing, valves, water heaters, storage tanks, expansion control, fixture supplies, cross-connection control, and testing.

Drainage and vent preparation may involve sanitary drainage, fixture-unit calculations, pipe sizing, slope, cleanouts, traps, vents, waste stacks, building drains, indirect waste, special waste, and protection against sewer gases.

Backflow preparation may include air gaps, vacuum breakers, backflow-prevention assemblies, cross-connections, installation conditions, testing access, and protection of potable water supplies.

Fuel-gas preparation may involve gas-demand calculations, pipe sizing, materials, appliance connections, shutoff valves, regulators, sediment traps, pressure testing, combustion air, venting, and equipment clearances.

Hydronic preparation may include boilers, pumps, circulators, expansion tanks, air separators, heat exchangers, valves, radiant systems, baseboard systems, controls, temperature regulation, pressure relief, and system balancing.

Fire-sprinkler preparation may involve sprinkler-system classifications, piping arrangements, water supplies, valves, hangers, fittings, testing, residential applications, commercial applications, and coordination with fire-protection plans.

Excavation preparation may include trench safety, underground utility locating, bedding, pipe support, backfill, compaction, dewatering, access, spoil placement, protective systems, and restoration.

Plan-reading preparation may involve plumbing plans, riser diagrams, isometric drawings, fixture schedules, equipment schedules, specifications, details, elevations, pipe sizes, slopes, symbols, and coordination with architectural, mechanical, electrical, and structural plans.

Estimating preparation may include pipe quantities, fittings, valves, fixtures, equipment, hangers, insulation, excavation, bedding, backfill, labor, testing, equipment rental, access, permits, waste, and project scheduling.

Passing the applicable examination does not automatically issue the C-37 contractor license. The Arizona Registrar of Contractors must review and approve the complete application before the business may advertise, bid, contract for, or perform work requiring the classification.

Open Book Test

The Arizona C-37 Plumbing trade examination is an open-book test using approved reference materials. Candidates are responsible for bringing the permitted books and following the testing provider’s current rules for editions, highlighting, annotations, permanent tabs, attachments, calculators, and book inspection.

An open-book examination still requires strong plumbing knowledge. Candidates must identify the system involved, determine the applicable code or trade subject, select the correct reference, locate the relevant provision, complete any required calculation, and apply the information within the examination time.

All books are highlighted and Tabbed. Highlighting draws attention to useful plumbing-code provisions, fuel-gas rules, mechanical requirements, sprinkler information, hydronic concepts, formulas, pipe-trade data, and OSHA safety standards. Permanent tabs support faster movement among major chapters and frequently researched topics.

The references should be used throughout the course rather than opened for the first time on examination day. Repeated navigation practice helps candidates become familiar with indexes, definitions, tables, diagrams, formulas, exceptions, and permanent tab locations.

Questions involving water supply, drainage, vents, fixtures, backflow prevention, interceptors, traps, storm drainage, or piping materials may require the International Plumbing Code. Fuel-gas questions may require the International Fuel Gas Code, while boiler and hydronic topics may involve the International Mechanical Code and the included hydronic references.

Fire-sprinkler questions may require the applicable NFPA sprinkler standard. Calculation questions may involve Mathematics for Plumbers and Pipefitters or IPT’s Pipe Trades Handbook. Excavation, trenching, tools, personal protective equipment, and construction-site safety questions may involve OSHA 29 CFR Part 1926.

Licensing Steps

1. Confirm the C-37 classification. Review the commercial plumbing scope to make sure it matches the services the business intends to provide.
2. Select the qualifying party. Identify the individual who will satisfy the applicable commercial plumbing experience and examination requirements.
3. Review the examination requirements. Determine which trade and Arizona Statutes and Rules requirements apply to the proposed qualifying party.
4. Prepare for the C-37 exam. Use the included course, highlighted and tabbed references, plumbing calculations, code-navigation exercises, and trade-focused review.
5. Complete the examination process. Pass the applicable trade examination and complete Arizona’s Statutes and Rules requirement unless an authorized waiver applies.
6. Form the business entity. Use the included Business Formation service to establish an LLC or corporation for the commercial plumbing business.
7. Obtain an EIN. Complete the included EIN Filing with the IRS for business banking, tax administration, payroll, employee hiring, and professional operations.
8. Complete applicable background requirements. Follow Arizona’s process for the individuals required to appear on the contractor application.
9. Prepare the application. Organize qualifying-party information, experience records, examination documentation, business documents, and required disclosures.
10. Obtain the commercial contractor license bond. Arrange the bond required for the commercial specialty classification and anticipated gross volume of work.
11. Submit the application. Provide the complete application and supporting materials to the Arizona Registrar of Contractors.
12. Wait for license issuance. Do not operate under the C-37 classification until Arizona approves the application and issues an active contractor license.

State Requirements

The C-37 classification is an Arizona commercial specialty contractor license. It does not provide residential plumbing contracting authority.

The proposed qualifying party must demonstrate the experience, knowledge, and skills needed to supervise or perform commercial plumbing work. Experience records may describe water piping, drainage, venting, fuel gas, fixtures, boilers, hydronics, fire sprinklers, excavation, commercial projects, estimating, and field supervision.

The qualifying party must remain associated with the applicant business in the capacity recognized by the Arizona Registrar of Contractors. Experience records, examination information, and the individual’s business role should remain consistent throughout the application process.

The legal business entity applying for the license must be properly established and identified. The company name, ownership information, qualifying-party records, EIN documentation, contractor bond, and application should remain consistent.

Arizona contractor applicants must complete applicable background and disclosure requirements and provide the identity, experience, examination, and business information required for state review.

A commercial specialty contractor license bond is required. The applicable amount is based on the anticipated gross volume of commercial work.

Because C-37 is a commercial-only classification, the residential financial-protection requirements associated with Arizona residential and dual contractor licenses do not apply.

After licensing, the contractor must remain within the authorized C-37 scope, maintain the required bond, renew the license, and keep qualifying-party and business records current.

Reference Books

• Included Book: Code of Federal Regulations – 29 CFR Part 1926 (OSHA)
  Covers excavation, trench protection, ladders, tools, electrical exposure, personal protective equipment, material handling, and commercial construction safety.
• Included Book: International Fuel Gas Code, 2018
  Supports study of gas-piping materials, sizing, appliance connections, regulators, shutoff valves, combustion air, venting, and pressure testing.
• Included Book: International Mechanical Code, 2018
  Supports preparation involving boilers, hydronic systems, mechanical equipment, piping, ventilation, access, and testing.
• Included Book: International Plumbing Code, 2018
  Covers water supply, drainage, vents, fixtures, traps, interceptors, backflow prevention, storm drainage, materials, and testing.
• Included Book: NFPA 13: Installation of Sprinkler Systems, 2019
  Supports preparation involving commercial sprinkler-system design concepts, piping, components, water supplies, installation, and testing.
• Included Book: NFPA 13D, 2019
  Addresses sprinkler systems for one- and two-family dwellings and manufactured homes.
• Included Book: NFPA 13R, 2019
  Addresses sprinkler systems for qualifying residential occupancies up to and including four stories.
• Included Book: Mathematics for Plumbers and Pipefitters, 8th Edition
  Supports trade calculations involving measurements, geometry, offsets, slope, volume, pressure, and piping applications.
• Included Book: IPT’s Pipe Trades Handbook, Robert A. Lee, 2016
  Provides practical pipe, fitting, flange, valve, dimension, weight, formula, and field-reference information.
• Included Book: Boiler Operator’s Guide, 5th Edition
  Supports study of boiler systems, controls, safety devices, operation, water treatment, inspection, and maintenance.
• Included Book: Arizona 811 – Arizona Blue Stake Brochure
  Supports preparation involving underground utility locating and safe excavation practices in Arizona.
• Included Book: Modern Hydronic Heating for Residential and Light Commercial Buildings, John Siegenthaler, P.E., 2022
  Supports study of hydronic system design, boilers, pumps, piping, heat emitters, controls, expansion, air removal, and system performance.

All books are highlighted and Tabbed.

The package includes a $1,100 refundable book deposit. The deposit is refundable when the books are returned within one year in similar condition.

Please allow up to 15 business days for The 1 Package book orders.

Test Information and Study Materials

Effective C-37 preparation should combine plumbing-code navigation, water-supply systems, drainage, venting, fuel gas, hydronics, fire sprinklers, excavation, calculations, plan reading, estimating, and OSHA safety.

Calculation practice may include pipe sizing, fixture units, slope, offsets, developed length, pressure loss, volume, area, flow, gas demand, hydronic loads, and material quantities.

System study may include water services, distribution piping, sanitary drainage, vents, storm drainage, fixtures, water heaters, backflow prevention, fuel-gas piping, boilers, pumps, controls, and sprinkler components.

Safety preparation should address trench collapse, underground utilities, lifting, hot work, pressure testing, tools, ladders, electrical exposure, personal protective equipment, material storage, and housekeeping.

How 1 Exam Prep Helps You Reach Your Goal

1 Exam Prep supports Arizona C-37 candidates through organized study guidance, trade-focused review, practice-oriented preparation, reference navigation, and confidence-building study structure.

The course divides commercial plumbing preparation into manageable subjects, including water supply, drainage, vents, fixtures, fuel gas, hydronics, fire sprinklers, excavation, calculations, plan reading, estimating, and safety.

Reference-navigation exercises help candidates identify the correct book, locate applicable chapters and tables, interpret code provisions, and connect calculations with installation requirements. Practice-oriented preparation strengthens both trade knowledge and exam-day research skills.

Application Service supports the Arizona licensing stage by helping organize qualifying-party information, examination records, business documents, and required application materials. Business Formation establishes an LLC or corporation so the customer has a legally structured commercial plumbing business.

EIN Filing with the IRS provides the federal identification number used to open business bank accounts, manage taxes properly, hire employees, and operate professionally. Contractor Compliance Guidance supports a clearer understanding of responsibilities associated with maintaining the license, bond, qualifying party, business records, and approved scope of work.

No preparation program or business service guarantees an examination result, licensing approval, earnings, or business success. The package provides the references, course access, application support, and business setup services needed to pursue the Arizona C-37 licensing path with stronger organization and confidence.

What is included in The 1 Package?

The package includes twelve plumbing, fuel-gas, mechanical, sprinkler, hydronic, mathematics, pipe-trade, excavation, and construction-safety references, 1 year of course access, Application Service, LLC or corporation formation, EIN Filing with the IRS, and Contractor Compliance Guidance.

What is the total cost?

The package cost is $3,315. A $1,100 refundable book deposit brings the total due to $4,415. The package is all-inclusive with no hidden fees.

How does the refundable book deposit work?

The $1,100 deposit is refundable when the books are returned within one year in similar condition.

Are all books highlighted and tabbed?

Yes. All books are highlighted and Tabbed to support organized study and faster reference navigation.

How long should I allow for the book order?

Please allow up to 15 business days for The 1 Package book orders.

Is the Arizona C-37 examination open book?

Yes. The Arizona C-37 Plumbing trade examination is open book using approved reference materials under the testing provider’s examination rules.

Does C-37 cover residential plumbing work?

No. C-37 is the commercial Plumbing classification. Residential plumbing work requires the appropriate residential or dual contractor classification.

Does the package include hydronic-heating preparation?

Yes. The included references support preparation involving boilers, pumps, piping arrangements, heat emitters, expansion control, air removal, controls, balancing, and system operation.

Does the package include fire-sprinkler preparation?

Yes. The package includes NFPA 13, NFPA 13D, and NFPA 13R references for sprinkler-system preparation.

Does the package include licensing and business setup?

Yes. The package includes Application Service, LLC or corporation formation, EIN Filing with the IRS, and Contractor Compliance Guidance.

Does passing the examination automatically issue the license?

No. The Arizona Registrar of Contractors must review and approve the complete application before issuing the C-37 commercial contractor license.