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Mechanical Types

Scope of Work

Allows for the installation and erection of steam and hot water boilers, pressure vessels, precipitators, incinerators, breeching, chimneys, plate and casings. The holder of this Certificate may perform this work only in the employ of a Boilermaker Contractor.

Testing

ICC Exam #F31 National Standard Journeyman Mechanical

Minimum Experience Required To Apply

  • Four (4) years boilermaker field installation experience in an apprenticeship or on-the-job training program completing a minimum of 7,000 hours.
  • Experience as a journeyman, supervisor, or contractor under a recognized licensing authority may be accepted on a year-for-year basis.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Form and Required Documents

Scope of  Work

Allows the holder to take charge of and operate all steam boilers and appurtenances, steam pumps, steam turbines and steam engines.

Testing

ICC Exam #F29 National Standard Master Mechanical 

Minimum Experience To Apply 

  • Three (3) years in boiler operating work as a trainee or apprentice on equipment producing over 100 hp and steam pressure over 100 p.s.i. and water heating systems when the water temperature exceeds 250 degrees F in the system.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Form and Required Documents

Scope of Work

Allows the holder to take charge of and operate all steam boilers and appurtenances, steam pumps, steam turbines and steam engines containing a steam pressure between 15 and 100 psi and where the equipment produces a total of between 10 and 100 horsepower at Denver altitude.

Testing

ICC Exam #F29 National Standard Master Mechanical

Minimum Experience Required To Apply

  • Three (3) years in boiler operating work as a trainee or apprentice on equipment producing a total of between 10 and 100 hp and steam pressure between 15 and 100 p.s.i. and water heating systems when the water temperature exceeds 250 degrees F in the system.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Application Form and Required Documents

Scope of Work

To install, assemble or repair steam and hot water boilers, all pressure and non-pressure vessels, precipitators, breeching, metal stacks, plates and casings. 

Testing

ICC Exam #F29 National Standard Master Mechanical 

Minimum Experience Required To Apply

  • Eight (8) years in boilermaker work consisting of the following:
    • Four (4) years field installation experience in a journeyman or on-the-job training program AND four (4) years experience as a designer or supervisor.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Form and Required Documents

Scope of Work

Allows for the installation of the following equipment utilizing gas or liquid fuel:

  1. Gas and liquid fuel piping. The low-voltage wiring permitted by this Certificate shall apply to gas or liquid fuel-fired appliances only. The holder of this Certificate may perform this work only when in the employ of a Gas Service Contractor or a Heating and Ventilating Contractor Class A or B.
  2. Gas and liquid fuel controls.
  3. Commercial cooking equipment.
  4. Afterburners.
  5. Ranges.
  6. Dryers.
  7. Conversion burners.
  8. Venting of domestic water heaters, dryers and incinerators.
  9. Water heaters not exceeding 100 Btu input.
  10. Low-voltage wiring that does not exceed 48 volts and is not enclosed in a conduit or raceway.

Testing

ICC Exam #F34 National Standard Journeyman Gas Pipefitter

Minimum Experience Required To Apply

  • Four (4) years gas service field installation experience in an apprenticeship or on-the-job training program completing a minimum of 7,000 hours.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Form and Required Documents

Scope of Work

To install, add to, alter or repair the following equipment, which utilizes gas or liquid fuel:

  1. Gas and liquid fuel piping.
  2. Gas and liquid fuel controls.
  3. Commercial cooking equipment.
  4. After burners.
  5. Ranges.
  6. Dryers.
  7. Conversion burners.
  8. Venting of domestic water heaters, dryers and incinerators.
  9. Water heaters not exceeding 100 MBtu input.
  10. Low voltage wiring that does not exceed 48 volts and is not enclosed in a conduit or raceway.  

Testing

ICC Exam #F33 National Standard Master Gas Pipefitter

Minimum Experience Required To Apply

  • Six (6) years in gas fitting work consisting of the following experience:
    • Four (4) years field installation experience in an apprentice or on-the-job training program completing a minimum of 7,000 hours;
    • Two (2) years field installation experience as a designer or supervisor.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Form and Required Documents

Scope of Work

Allows for the installation of 1) Heating and Ventilating - warm air heating, ductwork, ventilation and evaporative cooling, exterior sheet metal, water heaters not exceeding 100 Mbtu input, gas piping, burners, venting and controls, exhaust systems and appurtenances thereof, and low-voltage wiring that does not exceed 48 volts and is not enclosed in a conduit or raceway. 2) Air Conditioning – refrigeration systems and appurtenant cooling towers, pipe insulation and low voltage wiring which does not exceed 48 volts and is not enclosed in a conduit or raceway.

The holder of this Certificate may perform this work only in the employ of a Heating and Ventilating Contractor Class A or Heating Ventilating Air Conditioning Contractor.

Testing

ICC Exam #F31 National Standard Journeyman Mechanical

Minimum Experience To Apply

  • Four (4) years heating & ventilating field installation experience in an apprenticeship or on-the-job training program completing a minimum of 7,000 hours.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Form and Required Documents

Scope of Work

To install, add to, alter or repair warm air heating, venting, ventilation, evaporative cooling, exhaust systems and their appurtenances, ductwork, dust collection systems, domestic and commercial range hoods, water heaters not exceeding 100 Mbtu input, gas piping; burners, controls and venting, trash and laundry chutes; exterior sheet metal, duct insulation, low voltage wiring that does not exceed 48 volts and is not enclosed in a conduit or raceway and maximum of 50 tons of refrigeration when it is utilized for comfort cooling and the refrigerating system is self-contained. This refrigeration shall not include systems with precharged lines or separate air-cooled condenser or chilled water systems.

Testing

ICC Exam #F29 National Standard Master Mechanical

Minimum Experience Requirement To Apply

CLASS A (COVERS COMMERCIAL & RESIDENTIAL):

  • Eight (8) years in commercial heating & ventilating work consisting of the following:
    • Four (4) years as a heating & ventilating journeyman mechanic AND
    • Four (4) years in one or more of these positions: Designer, Draftsman or Supervisor.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Application Form and Required Documents

Scope of Work - Residential Only

To install, add to, alter or repair, in one- or two-family dwellings, IRC townhomes or U Occupancies only 1) Heating and Ventilating - warm air heating systems and their appurtenances, ductwork, ventilation, evaporative cooling, duct insulation, exterior sheet metal, gas piping; burners, venting and controls, water heaters not exceeding 100 Mbtu input and low voltage wiring that does not exceed 48 volts and is not enclosed in a conduit or raceway. 2) Air Conditioning – refrigeration systems of 5 tons or less. 

Testing

ICC Exam #F32 National Standard Residential Mechanical (Class C)

Minimum Experience Required To Apply

CLASS B (COVERS RESIDENTIAL ONLY):

  • Six (6) years in residential heating & ventilating work consisting of the following:
    • Four (4) years as a heating & ventilating journeyman mechanic AND
    • Two (2) years in one or more of these positions: designer, draftsman or supervisor.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Application Form and Required Documents

Scope of Work - Residential Only

To install, add to, alter or repair, in one- or two-family dwellings, IRC townhomes or U Occupancies only: 1) Heating and Ventilating - warm air heating systems and their appurtenances, ductwork, ventilation, evaporative cooling, duct insulation, exterior sheet metal, gas piping; burners, venting and controls, water heaters not exceeding 100 Mbtu input and low-voltage wiring that does not exceed 48 volts and is not enclosed in a conduit or raceway; and 2) Air Conditioning – refrigeration systems of 5 tons or less.

Testing

ICC Exam #F32 National Standard Residential Mechanical (Class C)

Minimum Experience Required To Apply

1. HEATING AND VENTILATING

Six (6) years in residential heating & ventilating work consisting of the following:

  • Four (4) years as a heating & ventilating journeyman mechanic AND
  • Two (2) years in one or more of these positions:
    • Designer
    • Draftsman
    • Supervisor

2. REFRIGERATION

Six (6) years in residential refrigeration installation work consisting of the following:

  • Four (4) years field installation experience in an apprenticeship or on-the-job training program completing a minimum of 7,000 hours AND
  • Two (2) years as a Designer or Supervisor.

3. Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.

  • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
  • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
  • List the address for each project mentioned.
  • List as many projects needed in order to cover the required amount of experience.

Application Form and Required Documents

 

Scope of Work

To install, add to, alter or repair, in one- or two-family dwellings, IRC townhomes or Group U Occupancy only, hot water heating systems and their appurtenances, solar water heating, water heaters, gas piping and controls, pipe insulation and low voltage wiring that does not exceed 48 volts and is not enclosed in a conduit or raceway.

Testing

ICC Exam #F32 National Standard Residential Mechanical (Class C

Minimum Experience Required To Apply

  • Six (6) years in steam and hot water installation work consisting of the following: 
    • Four (4) years field installation experience in a journeyman or on-the-job training program completing a minimum of 7,000 hours; AND
    • Two (2) years experience as a designer or supervisor.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Application Form and Required Documents

Scope of Work

To install, add to, alter or repair refrigeration systems and appurtenant cooling towers, pipe insulation and low-voltage wiring that does not exceed 48 volts and is not enclosed in a conduit or raceway. A permit or license is not required for the installation of self-contained window type air conditioners. 

Testing

ICC Exam #F29 National Standard Master Mechanical

Minimum Experience Required To Apply

CLASS A (COMMERCIAL & RESIDENTIAL):

  • Eight (8) years in commercial refrigeration installation work consisting of the following:
    • Four (4) years field installation experience in a journeyman or on-the-job training program completing a minimum of 7,000 hours; AND 
    • Four (4) years experience as a designer or supervisor.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Application Form and Required Documents

Scope of Work - Residential Only

To install, add to, alter or repair, in Group one- and two-family dwellings, townhouses and Group U Occupancies, refrigeration systems consisting of self-contained refrigeration systems of 5 tons or less, the installation of pre-charged systems utilizing Group 1 Refrigerants and gas-fired absorption chillers. All work to be done under on site supervision of a Class A or B Refrigeration Supervisor Certificate holder.

Testing

ICC Exam #F32 National Standard Residential Mechanical (Class C)

Minimum Experience Required To Apply

CLASS B (RESIDENTIAL ONLY):

  • Six (6) years in residential refrigeration installation work consisting of the following:
    • Four (4) years field installation experience in an apprenticeship or on-the-job training program completing a minimum of 7,000 hours; AND 
    • Two (2) years as a designer or supervisor.
  • Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.
    • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
    • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
    • List the address for each project mentioned.
    • List as many projects needed in order to cover the required amount of experience.

Form and Required Documents

Scope of Work

Permits the installation of refrigeration systems and appurtenant cooling towers, pipe insulation and low-voltage wiring which does not exceed 48 volts and is not enclosed in a conduit or raceway.  The holder of this Certificate may perform this work only in the employ of a Refrigeration Contractor Class A or B

Testing

ICC Exam #F31 National Standard Journeyman Mechanical

Minimum Experience Required To Apply 

Four (4) years refrigeration field installation experience in an apprenticeship or on-the-job training program completing a minimum of 7,000 hours.

Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.

  • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
  • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
  • List the address for each project mentioned.
  • List as many projects needed in order to cover the required amount of experience.

Application Form and Required Documents 

Scope of Work

Allows the holder to take charge of and operate mechanical refrigeration systems.

Testing

ICC Exam #228 Colorado (Denver) Refrigeration Operator

Minimum Experience Required To Apply

Three (3) years in refrigeration operation work as a trainee or apprentice on refrigeration systems of all types.

Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.

  • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
  • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
  • List the address for each project mentioned.
  • List as many projects needed in order to cover the required amount of experience.

Form and Required Documents

Scope of Work

Allows the holder to take charge of and operate all steam boilers and appurtenances hereto, steam pumps, steam turbines, steam engines and mechanical refrigeration systems.

Minimum Experience Required To Apply

Four (4) years in stationary engineering work consisting of a minimum of three (3) years operating high-pressure steam boilers producing over 10 hp and steam pressure over 15 p.s.i. or water heating boilers when the water temperature exceeds 250 degrees F in the system, and minimum of one (1) year operating refrigeration equipment requiring an operator per Chapter 1, Denver Building Code.

Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.

  • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
  • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
  • List the address for each project mentioned.
  • List as many projects needed in order to cover the required amount of experience.

Testing

ICC Exam #227 Colorado (Denver) Stationary Engineer

Application Form and Required Documents

Scope of Work 

To install, add to, alter or repair steam and hot water heating systems, solar water heating; process piping and related appurtenances; piping used for the transmission of chemicals, gases, air and other products; all items regulated by the Mechanical and Plumbing Code for boilers, pressure vessels, steam and water heating systems and process piping; low-static gas-fired unit heaters; industrial ovens; burners; controls; piping and controls utilizing gas, liquid or solid fuel; water heaters; pipe insulation and low-voltage wiring which does not exceed 48 volts and is not enclosed in a conduit or raceway. 

Testing

ICC Exam #F29 National Standard Master Mechanical

Minimum Experience Required To Apply

Eight (8) years in commercial steam and hot water installation work consisting of the following:

  • Four (4) years field installation experience in a journeyman or on-the-job training program completing a minimum of 7,000 hrs. AND
  • Four (4) years experience as a designer or supervisor.

Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.

  • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
  • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
  • List the address for each project mentioned.
  • List as many projects needed in order to cover the required amount of experience.

Application Form and Required Documents

Scope of Work

Allows for the installation of steam and hot water heating systems; solar water heating; process and industrial piping and related appurtenances; piping used for the transmission of chemicals, gases, air, milk and other products transmitted through piping; and all items regulated by the Mechanical and Plumbing Code for boilers, pressure vessels, steam and water heating systems and process piping; low-static gas-fired unit heaters; industrial ovens; burners, piping and controls utilizing gas; low-voltage wiring which does not exceed 48 volts and is not enclosed in a conduit or raceway; commercial cooking equipment; commercial incinerators; and afterburners. The holder of this Certificate may perform this work only in the employ of a Steam and Hot Water Contractor or a Hot Water Contractor. 

Testing

ICC Exam #F31 National Standard Journeyman Mechanical 

Experience Required

Four (4) years steamfitter field installation experience in an apprenticeship or on-the-job training program completing a minimum of 7,000 hours.

Notarized letter(s) must show WHAT, WHEN AND WHERE you gained the necessary experience for each project.

  • List exact scope of work, duties, projects performed, and equipment operated by the individual applying for the certificate.
  • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years.
  • List the address for each project mentioned.
  • List as many projects needed in order to cover the required amount of experience.

Application Form and Required Documents

 

FAQs

The online certificate application will require you to upload notarized letters of experience that document how you meet the minimum experience needed for that certificate type. These letters must come from owners or officers of current or previous employers, or clients that have hired you to do work. If you are the owner of the company, you must go to previous employers or clients that you have done work for as you can not be your own reference.


Notarized letters should be in the following format:

  • Original notarized letters. These can be scanned and uploaded if applying online.
  • If a company is verifying your experience, the letter should be typed on company stationary.
  • List exact duties, projects performed and equipment operated.
  • List exact start and end dates (month and year) of construction work only for each project. Projects should have been completed within the last ten (10) years. Use the following format:  
    Start Date:  MM/YY, End Date:  MM/YY.
  • List the address for each project mentioned. 
  • Include letters from previous or present employers or customers who have hired you to do the type of work covered by that certificate. 
  • Do not submit letters from other officers / members of your company, subcontractors, or family members.
  • Submit as many notarized letters as needed to document the minimum experience requirements for the certificate you are applying for.
  • Retain copies of your application and notarized letters. The Contractor Licensing office will not be able to make additional copies for you.

Colorado Revised Statutes require that applicants submit an Affidavit of Lawful Presence and Secure and Verifiable Identification as proof that they are lawfully present in the United States. 

Complete the Affidavit of Lawful Presence (PDF) and upload it with your certificate application.

  • Alternatively, mailed certificate applications must have the Affidavit of Lawful Presence and a Secure and Verifiable Identification notarized.
  • If you are submitting your application in person to the Contractor Licensing office, you may fill out the Affidavit in the presence of Contractor Licensing staff and present an original form of identification.
  • If you are submitting an application for another person, you must have the Affidavit of Lawful Presence and a Secure and Verifiable Identification notarized.

Once your application is submitted online, it will take approximately 7 to 10 business days to be reviewed. You will receive an approval or denial email once the application has been reviewed, and will then be able to return to the online application to pay for the certificate.

Mail-in applications can take up to 14 business days to be processed. Do not submit payment with your application. You will be notified by telephone of application approval or rejection. (Please note that the Contractor License office can only give application status to the actual applicant.)


In the event that your application is not approved, you will be given the opportunity to apply a second time. Additional documentation is required. 

However, if the application is not approved the second time, there is a six-month waiting period before applicants can re-apply for the same certificate type.


For Specialty D Certificates:

If your application is approved, you will have 90 days to procure your certificate by paying the appropriate fee amount. Specialty D certificates are valid for 3 years.

  • Please return to your online certificate application to pay fees.

For Certificate Requiring ICC Testing:

If your application is approved, you will have 90 days to procure your certificate by submitting the official ICC pass letter and your payment.


Approved supervisor certificate holders may now apply online for a contractor's license.