Commissioning Training - Thomas Stuenkel

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What is Commissioning?

What is Commissioning?

What is Commissioning? And related terms?

What is Commissioning, Pre-Commissioning, P&ID Checking, Mechanical Completion, Start-Up, Initial Operation, Performance Testing, Post Commissioning, Cold Commissioning, Hot Commissioning, Dry Commissioning, Wet Commissioning, Live Commissioning, …?

A lot of different technical terms. Do you know what they mean? No? Or just a few? Ok, read on.

I prepared a mind map (you know, the format which makes it easier for you to remember things) with all these commissioning related terms. You can download the mind map “What is Commissioning?” below after unlocking the download link by liking it on Facebook, Google+ or sharing it on LinkedIn.

But for now – just grab a cup of coffee or tea, switch off your mobile phone and watch the commissioning training video below with an explanation about “What is Commissioning?” and all of the above mentioned commissioning related terms.

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If you like you can watch the same commissioning training video on YouTube as well.

Do you want to download this commissioning training video including the mindmap? Just enroll for free into this course (and as well free into my commissioning training course “The 9 Key Elements of Successful Plant Commissioning”) on now. Just click here.

Download the “What is Commissioning?” mind map PDF for FREE now

What is Commissioning?

What is Commissioning?
Click the mind map above to download your free PDF now!

Do you have questions?

Your comments, thoughts and questions about the short commissioning training video are appreciated in the comments section below!

Talk soon,

Thomas Stuenkel

PS: Did you miss a commissioning term in this mind map? Do you use other terms to describe certain commissioning activities?  In which industry do you work? Oil & gas, power, renewable energy, petrochemical, chemical, nuclear, mining, water, pharmaceuticals, biotechnology …? It would be great if you can share this in the comments section below.

Video Transcript “What is Commissioning?”

What is commissioning? What is cold commissioning, what is hot commissioning, dry commissioning, wet commissioning, static commissioning, life commissioning? We will answer these questions and a few more in about 30 seconds.

Hello everybody. My name is Thomas Stuenkel. I’m the founder of, a commissioning engineer, commissioning manager and commissioning coach. I have prepared a mind map for you on my computer. It’s an explanation of these commissioning related terms. Let’s start with the presentation.

What is commissioning and an explanation of related terms. But before I start, here is an important note. The intention of this document is to bring a little bit of light into different terms used worldwide by different companies. Something like, to find a common denominator. Maybe your company understands for example, wet commissioning completely different than your friend’s company or what I’m explaining here. This is okay. Just use the documents and terms used by your company.

Before we come to the explanation of commissioning , I want to explain other related terms in the logical sequence. The first field activity for a commissioning engineer or commissioning manager is the P&ID checking. This means, a system check for engineering and construction errors after handing over a system or sub-system from construction team to the commissioning team or we can say, this is the system check. This is another synonym for P&ID checking or we can say, walk down … another synonym or we can say punching and a punch list is created during this P&ID checking or walk down or system check or punching.

Mechanical completion. This means checking and testing of equipment and construction to confirm that the installation is in accordance with drawings and specifications and ready for pre-commissioning or commissioning in a safe manner and in compliance with project requirements. The “or” is in capitals and bold because mechanical completion can mean ready for pre-commissioning or commissioning and this depends only from the definitions in the contract – but this is another training lesson.

Pre-Commissioning. Pre-Commissioning activities usually start after the system achieved mechanical completion. Pre-Commissioning activities include, flushing and cleaning, drying, leak testing, running-in of equipment and something more. Sometimes pre-commissioning activities are included into mechanical completion but this depends again on the contract definitions. In our API 1 FSC, the term pre-commissioning is there named with static commissioning.

Now we are coming to the term cold commissioning. Cold commissioning consists of two different other terms again. This is dry commissioning and wet commissioning. Dry commissioning – These are tests and procedures that are conducted without solvents or process fluids yet introduced to the plant. For example, control system sequence tests. Wet commissioning, it means water or a solvent has been introduced into the system and sub-systems. Tests and procedures conducted with water or solvents. A solvent is a medium which is not as dangerous as the process fluid but the other specifications are closed to the process fluid and what we are doing there is operating scenarios. For example we are running pumps in closed loops.

Hot commissioning. This means, design process fluids are introduced in the systems and sub-systems and again we are doing here operating scenarios.

Live commissioning. This is the synonym for hot commissioning.

Now we are coming to the term commissioning. The common term commissioning. What does it mean? Commissioning is usually the phase in a project when design process fluids are introduced to the systems and sub-systems. Sometimes commissioning means running the systems with a safe fluid only.

Next step after commissioning is our PSSR, Pre-Start-up Safety Review and we are doing this together with the client, the contractor, sometimes the PMC and the licensor.

Next step is the start-up. The phase in the project where the entire plant – all systems and sub-systems – are taken into operation. Process fluids are introduced and process conditions are established with the intent of making products.

Initial operation. This is the phase in a project after the start-up of the complete plant in order to adjust, tweak, optimize and prepare the plant for the performance testing phase which is the next step.

Performance testing. Check if the plant meets the specifications under normal operating conditions.

The term “post commissioning” means solving of outstanding punch points after the plant has been handed over to the client.

At the end of the life cycle of a plant, de-commissioning. De-commissioning means taking out of active use and dismantling of an industrial plant.

Great. You watched the entire video. Now, just click the red button below this video and enroll into the free online commissioning training session “What is Commissioning?”.

Thank you very much for watching. Have a great day. Bye bye.

Thomas Stuenkel.

Leave a Comment

  • Goutham krishna October 13, 2019, 4:05 pm

    Thank u very much sir,it is quite helpful to get overall idea about commissioning

  • Christian Ferrer February 16, 2021, 2:00 am

    Great explanation of the stages. It turned out to be very very useful. Explained in simple but technical terms. Thank you very much.