DATA CENTER | 0, 1, 2, 3, 4, 5, 6 & 7 Levels of Commissioning

May 22, 2023 |

When we look at commissioning a data center, in most cases, there will be a project requirement to structure the process into five stages, commonly referred to as ‘Levels.’ So what are the 5 levels of commissioning?:

  • Level 1 – Red Tag – Factory Testing [Off Site]
  • Level 2 – Yellow Tag – Component and System Delivery / Pre-Installation [On Site]
  • Level 3 – Green Tag – Pre Commissioning / Pre Functional and Startup [On Site]
  • Level 4 – Blue Tag – Component / System Functional Performance Testing [On Site]
  • Level 5 – White Tag – System Integrated Testing [On Site]

The five levels, when we look at them in-depth, actually do not cover the whole process that we need, so there can be instances where clients and the commissioning agent / commissioning team overseeing the process modify, tweak and add three additional stages:

  • Level 0 – No Tag – Design and Planning
  • Level 6 – No Tag – Closeout and Turnover / Handover
  • Level 7 – No Tag – Acceptance of Final Reports and Documents

Are the 5 Levels the same as the ASHRAE Cx Process?

Although the process is similar, they are also different – generally we find that the ASHRAE process [Guideline 0] is more structured and has clear goals of documenting and ensuring that the commissioning process is conducted and any ongoing commissioning throughout the building life cycle is maintained.

The Data Center Levels 1 to 5 or 0 to 7, are more focused at commissions sequence, systems and equipment, with some documentation included. There is not much in the way of ongoing commissioning.

The best solution is to merge the 2 to get a global delivery taking the best bits of both, which we have done in our checklists and steps as detailed below and in our other articles.

In case you are wondering, here is our article explaining the Commissioning Process in line with ASHRAE Guideline 0.
Data Center Commissioning Checklist [MS Word] & [MS Excel]

Here is our open copy [MS Word] & [MS Excel] of the Data Center Commissioning Checklist, for making life a little easier...

#CC: 066
Buy Here | $1.99

Why use Commissioning Levels?

The purpose of utilizing the levels is to allow the project to focus on the commissioning and control the outcome, maintaining the quality assurance that the client usually requires.

Using the levels as a base, a complete process and structure can be developed via flow diagrams, responsibility matrices, and programs, using each stage as a ‘gate’ that needs to be completed before moving onto the next stage.

Can a Data Centre be Commissioned not using the Levels?

Yes, using the levels will not guarantee that the project will be commissioned correctly; a data center can achieve the same outcome of commissioning if a ‘general’ commissioning process is implemented that would be used on an Office-type building.

The levels do not guarantee a quality-orientated process; they just provide the base to work from and lay down the expectations for the project to start from.

If we think about it, when we commission a Chiller control system in an office vs. a data center, we would usually complete similar testing [maybe minus the part-load testing in the office due to site constraints].

What are these colored tags about?

Colored tags are used to provide a visual indication of the status of the system and components during the project construction and commissioning phases.

  • Level 0 – NO TAG
  • Level 1 – RED TAG
  • Level 2 – YELLOW TAG
  • Level 3 – GREEN TAG
  • Level 4 – BLUE TAG
  • Level 5 – WHITE TAG
  • Level 6 – NO TAG
  • Level 7 – NO TAG

Information to be displayed on the Tags

The information that would usually be contained on each tag would be:

  • Appropriate color
  • Level number
  • Level reference
  • Equipment ID
  • Project number
  • Date
  • Contractor/vendor signature box
  • Designer signature box
  • Commissioning Agent signature box
  • High-level description of the tag and next step
If want to see a typical checklist for commissioning a data center checkout our article DATA CENTER | Commissioning Checklist

Level 0 – Design and Planning

This is the start of the levels and would equate to the pre-design / design stage responsibilities within the standard commissioning process.

Tasks that should be completed during this level would be:

  •  Assemble the Commissioning Team.
  • Write, create, and manage the project requirements for the owner.
  • Create and maintain a basis of design document (BOD).
  • Create a budget and scope for the commissioning project.
  • The commissioning program should be written and developed.
  • Formats for commissioning reports should be developed.
  • Specify and manage the acceptance criteria.
  • Organize the commissioning documentation and finalize.
  • Determine the training requirements.
  • Complete and issue reports.
  • Conduct meetings and workshops.
  • Perform commissioning evaluations/commissioning design review based on the design and project details.
  • Create checklists.
  • Select any software that is to be utilized to aid/monitor the commissioning.
  • Develop a high-level commissioning strategy.
  • Create a high-level training programme.
  • Create a framework and format for the operation and maintenance manual.
  • Interacting with the general/main contractor.

There will be NO TAGS provided on completion of this stage.

To read our 40 STEP GUIDE for delivering Level 0, see our article | LEVEL 0 – DATA CENTER COMMISSIONING | Design & Planning

Level 1 – Factory Testing

Factory testing will usually be performed before any major/critical equipment on a project is delivered to the site to confirm that it fulfills its intended operating requirements, as the design stipulates.

The test will compare the equipment’s performance in the factory to its stated manufacture and operating data within a laboratory-type environment, which will be contained in the technical/material submission or on its equipment datasheets.

Once the factory witness testing has been completed satisfactorily, it will then be approved by the commissioning authority to be transported and delivered to the site for installation.

We have written more detail regarding Factory Acceptance Testing in our Article  A Complete Guide To Factory Acceptance Testing

The equipment will be provided with a RED TAG for verification of level completion and signed by the contractor/vendor, designer, and commissioning agent.

To read our 11 STEP GUIDE for delivering Level 1, see our article | LEVEL 1 - DATA CENTER COMMISSIONING | Factory Testing

Level 2 – Component Verification and Pre-Installation Checks

Once the equipment and components have been transported to the site and before acceptance of the delivery for offloading, verification/delivery checks should take place to ensure that the items delivered match what was ordered and that they meet the project requirements.

After these checks have been completed a ‘Storage Check and Pre-Installation Check’ should be completed to ensure the project process is adhered to and documented.

These checks are usually recorded via checksheets and form part of the overall process.

We have written more on delivery checks in our article 3 Types of Commissioning Checklists, in the section for the construction checks, we cover the delivery requirements for various systems and equipment.

The equipment will be provided with a YELLOW TAG to verify level completion and signed by the contractor/vendor, designer, and commissioning agent.

To read our 8 STEP GUIDE for delivering Level 2, see our article | LEVEL 2 – DATA CENTER COMMISSIONING | Component Delivery

Level 3 – Pre Commissioning / Pre Functional Testing

Level 3 will be centered around checking that the installations completed by the general contractor and vendors have been appropriately installed and align with the drawings, construction information, design requirements, code compliance, and manufacturers’ guidelines.

Once the system has been verified to have been installed correctly, the pre-commissioning / pre-functional and startup testing should occur.

All should be fully documented and form part of the overall structured process.

There will be a few steps integrated into this level:

  • General system installation checks [pipework/ductwork/cabling etc].
  • Equipment installation checks.
  •  Pre-commissioning / pre-functional checks and tests for items that are required for the future commissioning works [complete power testing through to pumps etc, pressure testing, pipework cleaning etc].
  • Energize Systems for pre-functional and start-up works to complete.
  • Manufacture startup tests and checks.
  • Ensuring systems are ready for the next stage of functional and site acceptance testing.
To read our 7 STEP GUIDE for delivering Level 3, see our article | LEVEL 3 – DATA CENTER COMMISSIONING | Pre-Functional/Start-Up

The equipment will be provided with a GREEN TAG to verify status completion and signed by the contractor/vendor, designer, and commissioning agent.

Level 4 – Component / System Functional Performance Testing

Upon completing the Level 3 inspections and startup testing, the process will move onto Level 4, the functional performance and site testing. This level’s quantity of work and coordination requirements should not be underestimated.

Huge, huge amount of work and why it is paramount that this level is planned out very early within the project. Anything hanging over from the previous levels could seriously impact, so best to have them all completed and signed off before moving to this step.

Over the completion of this level, various systems will be brought together and integrated to allow the commissioning agent and project team to verify they are operating as per the project requirements.

The strategy to deliver this stage should be detailed within the commissioning programme to ensure that everyone knows their roles as many different contractors and vendors will be involved.

Buy All 122No. Site Commissioning Documents

We have been asked several times to create a complete document package covering everything we have uploaded to the site.

So it's taken some time, but here it is....122No. Documents for you to download in Microsoft Word, Microsoft Excel & PDF Formats.


#CC: 000d
Buy Here | $89.99

A failure of any one of them could critically impact the whole project programme.

For example, a high-level process to fully commission and verify the operation of the CRAH Units [computer room air handling units] in a data hall would be something like:

  • Permits to works is in place [electrical/mechanical/drainage etc].
  • Any integrations with existing systems are understood and planned for.
  • All power circuits have been tested and are energized from the utility through to CRAH Distribution board and then through to the units themselves.
  • All switchboards have been tested and are energized through to the CRAH distribution board.
  • All electrical systems have been earth tested.
  • All drainage systems including local condensate, have been tested and signed off.
  • All pipework systems have been weld tested.
  • All pipework systems have been pressure tested.
  • Pumps are available and operating.
  • Chillers are available and operating.
  • The condenser system is available and operating.
  • Load is available in the spaces being cooled [data halls, UPS rooms etc]
  • All pipework systems have been chemically cleaned.
  • All CRAH have been backflushed.
  • All insulation has been applied in line with the specification and is vapor sealed.
  • Chilled water circuits have been hydrostatically water balanced.
  • Flooring/ceilings/containment systems [hot aisle/cold aisle] have been completed and tested.
  • Floor grilles have been installed where required and balanced.
  • All doors are installed and air-tight.
  • All wall and floor penetrations have been fire stopped to stop any potential air leakage/infiltration to/from the space.
  • CRAH controls and sensors are installed, calibrated, and operating
  • CRAH has been pre-commissioned and set up including all settings and any automatic valves being set up.
  • BMS system and controls are integrated and operating to allow all points to be verified back to the head end and graphics.
  • Fire systems are available for any tripping and alarming

As we can see, just in the above process, there will be input throughout Level 4 from:

  • Health and safety department
  • Permit office
  • Client team
  • Commissioning agent
  • Designer
  • General/main contractor
  • Flooring contractor
  • Fire stopping contractor
  • Fire contractor
  • Electrical contractor
  • Switchboard vendors
  • Pipework installation contractor
  • Insulation contractor
  • Pump manufacturer
  • Chemical cleaning contractor
  • Water balancing contractor
  • Plumbing and drainage contractor
  • BMS contractor
  • CRAH vendor
To read our 14 STEP GUIDE for delivering Level 4, see our article | LEVEL 4 – DATA CENTER COMMISSIONING | Functional Testing 

The equipment will be provided with a BLUE TAG to verify level completion and signed by the contractor/vendor, designer, and commissioning agent.

Level 5 – Integrated System Testing

The whole buildup through the levels is for this final step, the testing of the integrated system.

It is all the hard work is about when it comes to the overall construction of the data center – it’s not just the MEP contractor that is responsible; it’s the designer, contractors, vendors, building contractors, commissioning contractors, etc.

This level and documentation should be seen as being worth the project’s total value because if it fails, the data center will not be signed off, and the client will generally not be able to use or rent the space.

Understanding why a data center fails can cause a major headache and cost everyone involved a lot of money.

During this level, the focus will be on proving that all systems can work together and meet the expected design and project requirements.

The testing will usually cover the Mechanical Systems, known as the ‘Heat Load Test,’ and the Electrical Systems, known as ‘Electrical Integrated Testing.’

They are usually conducted separately as they have slightly different goals.

Heat load testing is completed to prove that the thermal response of the data hall under different heating load conditions and failure scenarios are within the tolerances stipulated by design. 

Electrical Integrated Testing is completed to prove that upon certain failures across the electrical systems and incoming utility supplies, the use of the data center will not be affected and will maintain its operating status with no downtime.

Some high-level tasks that will be completed during this stage usually involve:

  • Ensure testing scripts are fully approved by all parties with the testing outcomes being fully understood.
  • If conducting these tests on a new installation but using existing client systems such as chillers etc, discuss and plan with the relevant parties.
  • Ensure that everyone understands their roles to deliver successful testing, and are available.
  • Ensure that the previous functional testing of all systems has been completed and signed-off.
  • Ensure that the correct instruments and equipment are available to monitor and capture data from the testing.
  • Ensure that the correct temporary load is available and can be stepped in the correct increments.
  • Agreement on size of temporary loaders to be used.
  • Agreement on installation method and positioning of temporary loaders.
  • Agreement on wiring and power arrangement of loaders.
  • That all instruments and equipment are set up and ready for testing, with locations being agreed upon across the project.
  • Instruments and equipment have appropriate calibration certification.
  • Checking that spaces are completed and clean.
  • If having specific screens built for capturing data and allowing review during the testing, ensure that these are created and developed ready for the Level 5 testing.
  • All pre-requisites, as detailed within the approved scripts are managed and completed.
  • Conducting the testing in a controlled manner.
  • Capturing data from the testing [BMS, sensors, loggers etc].
  • Full download of data from BMS and sensors upon completion of the testing.
  • Writing and approval of the full detailed report on the testing completed.
To read our 16 STEP GUIDE for delivering Level 5, see our article | LEVEL 5 – DATA CENTER COMMISSIONING | Integrated Testing

The equipment will be provided with a WHITE TAG to verify level completion and signed by the contractor/vendor, designer, and commissioning agent.

Level 6 – Close out / Turnover / Handover

Some clients will request this level to allow a controlled closeout of the project; it will usually involve creating a handover document and working through it.

The document will detail the process that will be implemented to allow the client to accept the project and testing information that proves the systems and data hall are operating in line with project expectations and specified design criteria.

To read our 9 STEP GUIDE for delivering Level 6, see our article | LEVEL 6 – DATA CENTER COMMISSIONING | Closeout & Turnover

Tasks during this level would usually include:

  • Running the closeout process as stipulated by the document
  • Closing out and resolving defects
  • Completion of any additional testing that may be required
  • Client acceptance that the systems and data center have been proved to be operating as per the project requirements and design.

There will be NO TAGS provided on completion of this stage.

Data Center Commissioning Checklist [MS Word] & [MS Excel]

Here is our open copy [MS Word] & [MS Excel] of the Data Center Commissioning Checklist, for making life a little easier...

#CC: 066
Buy Here | $1.99

Level 7 – Acceptance of Final Reports and Documents

Once all the above levels have been completed, any outstanding documentation will be completed/updated and issued for final approval.

The client should accept the documentation and that the project has been fully delivered and handed over.

Documentation would involve:

  • Ensuring all Level 1, 2, 3 & 4 testing documents and data are approved and accepted.
  • Level 5 report is complete and accepted.
  • Level 6 closeout process completed.
  • Final commissioning report issued and accepted.
  • Operating and maintenance manuals are complete and approved.
  • Final sign-off certificate issued and returned approved.
To read our 2 STEP GUIDE for delivering Level 7, see our article | LEVEL 7 – DATA CENTER COMMISSIONING | Acceptance

There will be NO TAGS provided on completion of this stage.

Level 0 to Level 7 Data Center Commissioning Checklist

To help us expand the site and create more resources, we have created the below documentation in [Microsoft Word] & [Microsoft Excel] for download.

Click the ‘Buy It Now‘ button to purchase the fully editable copy of the document below, which can be used straight away.

You will direct to our shop page.

Related Articles

⬛ Latest Articles

⬛ Author

If you would like to know more about the author, here is my Personal Linkedin Account