By: Gerry Creaner B.Chem Eng. and Donagh Fitzgerald B.Prod Eng. Last Updated: January 2025

The purpose of IQ OQ and PQ is to create a documented evidence trail that proves that the equipment ordered has been delivered, installed properly and configured correctly and that the entire system is operating under load as per the engineering drawings and design specifications.

This proof can be on paper or electronic and must include signatures from key departments, such as Validation, Engineering, Maintenance, Calibration, Quality Assurance, etc. This documentation proves to the owners/clients or regulatory agencies that have jurisdiction over that facility that everything meets the required standards.

1) Installation Qualification (IQ)

• This is the first step.
• It checks that the equipment, piping, and components are:
  • Delivered correctly.
  • Installed properly.
  • Configured to meet the manufacturer’s or approved standards.
• Compares the design specifications (“what was specified”) to the actual on-site conditions (“what was found”).

2) Operational Qualification (OQ)

• Follows IQ.
• Tests if the equipment and systems work as expected. For example:
  • Does it run at the right speed?
  • Does it heat or cool to the right temperature?
  • Is the motor moving in the correct direction?
• Confirms the equipment operates within the limits set by the manufacturer.

3) Performance Qualification (PQ)

• Comes after IQ and OQ.
• Confirms the equipment is fit for its intended use as described in the User Requirements Specification (URS).
• Tests the equipment under actual working conditions to make sure it performs as required.

Each of these procedures can be standalone documents or combined (i.e. IQ and OQ can be combined into IOQ. In other situations, PQ may be combined with OQ or combined with Process Validation or Process Performance Qualification). However, in every case, the protocols need to be prepared specifically for the system or equipment being qualified.

These sequential steps are collated in an Equipment Qualification Protocol which is a written plan that states how qualification will be conducted.

The protocol is written for each critical system and outlines the steps and measurements required, what proof is needed, what the expected outcomes are, and what should be done if actual outcomes deviate from this.

If you need to learn how to populate an IQ IQ PQ equipment qualification protocol, check out our Equipment Validation (IQ OQ PQ) Training Course – For Starter Validation, CQV and C&Q Roles.

And if you would like a more in-depth look at IQ OQ PQ, keep reading…

Jump to section

• Why is IQ OQ PQ critical for product quality and patient safety?
• What is IQ or Installation Qualification?
• What is OQ or Operational Qualification?
• What is PQ or Performance Qualification?
• What is the V-Model?
• What is an Equipment Validation Protocol?
• Write and develop the protocol
• Execute the protocol

Two main reasons.

1) It’s a regulatory requirement

According to the Food and Drug Administration (FDA)

“Equipment used in the manufacture, processing, packing, or holding of a drug product shall be of appropriate design, adequate size, and suitably located to facilitate operations for its intended use and for its cleaning and maintenance.” – 21 CFR Title 211.63,

Do note that while the FDA deems equipment qualification essential in pharmaceutical manufacturing, it does not provide detailed instructions for how this should be carried out. Instead, it’s the responsibility of each company to ensure their equipment is well-designed, cleanable, and maintainable, and to prove its effectiveness and fitness for use. The exact methods used to qualify each piece of equipment, system or utility system are a choice made by each individual company. 

Within the EU, EudraLex – Volume 4 – Good Manufacturing Practice (GMP) provides more detailed guidance on qualification under Annex 15: Qualification and Validation

And while not regulation, ISPE Baseline Guide 5 Commissioning and Qualification (Second Edition) is a widely used guide in qualification that enjoys the support of numerous regulatory authorities.

2) Product Quality and Patient Safety

When qualifying and validating a new plant or process, even the slightest installation error or a trivial problem with equipment performance can cascade and escalate into serious product quality problems, potentially harming or even killing patients. This problem is especially acute with new or untested systems where there is no performance history to rely on and even tiny problems can have severe consequences.

So we use the IQ OQ PQ process to:

1. Create a documented evidence trail to show that the mechanical or piping system is installed correctly, meets the design specifications and produce consistent, reliable results under load.
2. Prevent installation, operational and performance errors.
3. Guarantee reliable performance and consistent production of high-quality products.

Qualification is usually done by the engineering group, the validation team or any other person or group that is qualified and knowledgeable on the use and operation of the equipment, and has the training and experience to perform the tasks required.

Click here for some more examples of professional IQ Templates for equipment installation verification, instrument installation verification, piping instrumentation verification and a P&ID walkdown template.

Operational qualification is a documented testing process to make sure that the equipment and systems operate as defined in the design stage and are within the operating ranges listed by the manufacturer.

This is the next step and confirms that the equipment operates as intended.

To conduct OQ, Commissioning and Qualification (C&Q) engineers collaborate with maintenance staff and engineers from various disciplines, including process, chemical, automation, instrumentation, and mechanical. They follow a detailed test plan to:

1. Test the equipment.
2. Document the results.
3. Compare and verify performance against the design specifications.

Features Commonly Tested in OQ:

• Temperature Control Systems
• Overheating/Low-Temperature Alarms
• Pressure Control Systems
• Fan/Motor Speed (RPM)
• Display Units/Human-Machine Interface (HMI)
• Operational Signals
• Servo Motor Accuracy
• Pressure Switches
• Level Switches

Testing Methods:

• Simple Tests:
  • Sending power to the equipment.
  • Opening and closing ports and valves to verify signal and switch functionality.
  • Checking components for proper operation.
• Complex Tests:
  • Pressure tests.
  • Flow tests.
  • Equipment interlock testing.
  • Speed tests.

Performance Qualification (PQ) confirms that equipment and systems meet the user’s needs and are suitable for their intended use, as defined in the User Requirements Specification (URS). It is the final step in equipment qualification.

How PQ Differs from OQ

While similar to Operational Qualification (OQ), PQ tests the equipment under real-world conditions, meaning it operates with a load or process medium, replicating the actual conditions it will experience during production.

Why PQ is Important

This phase ensures that all components of the equipment work together as a cohesive system. By testing under real operating conditions, PQ can uncover faults that might not be evident during earlier qualification phases. These issues include:

• Excessive vibration or noise: Caused by resonance when multiple vibrating components interact.
• Overheating: Often due to improperly aligned or tensioned driving belts.
• Process media backflow: Resulting from incorrectly sized or installed pipework.
• Pressure differentials: Caused by issues like faulty valves, other equipment, or backflow.
• Compound faults: Small issues combining to create significant operational problems.
• Operational inconsistencies: Variability in performance during processes such as mixing, blending, or granulation.
• Product quality issues: Including chemical impurities, incorrect particle sizes, or problems with content uniformity.

Key Focus of PQ

• Ensures the equipment performs consistently and reliably under actual production conditions.
• Identifies and resolves any operational issues that could affect product quality or process efficiency.
• Verifies that the system as a whole meets the defined specifications and requirements.

Performance Qualification must not be confused with Process Validation (PV) (verification that good product is made) or with cleaning validation and analytical methods.

The V-model is a method used to visualize and compare the relationship between the user requirements, functional design and detailed design to the installation qualification (IQ), operational qualification (OQ) and performance qualification (PQ) performed on them (see diagram below).

To implement, you start at the top left with user requirements, work down the left hand side of the V, and then up the right hand side, ending at PQ.

The left-hand side of the V represents what you want the system to do and how you’ll achieve that . The right-hand side of the V represents how you test the system to confirm that the system is fit-for-purpose (i.e. will make safe medicines for patients).

In pharmaceutical manufacturing, most companies and organisations follow the ISPE’s V-Model (ISPE Baseline Guide Volume-5) to validate their systems as it meets the requirements of the industry regulators such as the Food and Drug Administration (FDA) or the European Medicines Association (EMA).

An Equipment Qualification Protocol is a written plan stating how the qualification process will be conducted. It includes a component-level impact assessment, the steps to perform IQ OQ and PQ, test parameters, product characteristics, production equipment and decision points on what constitutes an acceptable result.

It details factors such as:

• Test scripts and methods – telling you the steps involved in conducting a test
• Test parameters and acceptance criteria – defining acceptable test results
• Product characteristics – showing what your system is looking to achieve/produce
• Production equipment – detailing the equipment necessary
• Final approval – documenting that the validation process has been successfully carried out

This flowchart provides a broad overview of the process used to gain approval to execute the protocol and shows the expected time and responsibilities for developing it.

Image: Equipment Qualification in the Pharmaceutical Industry by Steven Ostrove

Not every protocol needs to follow this specific path or the indicated timeline (often depending on whether the protocol is prepared in-house or by an outside firm) but there are some general approaches and steps that have proven successful over the years that you’re likely to see included.

It can be useful to think of a qualification protocol as a highly detailed checklist with 2 steps.

Step 1: Write and develop the protocol

This is a detailed document and contains the elements outlined above. This step is usually performed by a senior validation engineer, CQV or C&Q specialist and requires a lot of experience and detailed knowledge of the process.

Pre-preparation checklist

1) Perform a systems-level impact assessment to make sure you are only qualifying systems that have a direct or indirect impact on product quality and patient safety.

2) Get a thorough understanding of the unit’s function. You must understand the unit’s function and its intended use. If a unit has multiple functions, only those being utilized for the current operation need to be qualified. This includes ensuring that unqualified functions do not interfere with the operation of the qualified ones.

3) Inquire from the users (if possible) about the system’s expected specific function.

4) Gather necessary documents such as equipment manuals, URS, functional specifications, design specifications, and standard operating procedures (SOPs).

Documents needed for IQ OQ PQ preparation

5) Review the Process Flow Diagram (PFD) to grasp the overall process flow.

6) Review the Piping and Instrumentation Diagram (P&ID) to confirm the system boundaries. Each qualification protocol must represent a stand-alone system capable of operating independently. An example of such a system is a Clean In Place System, which, despite having many internal components crucial for its operation, presents itself as a complete unit. Below is an example of the boundaries drawn in yellow around a Clean-In-Place system.

7) Review the commissioning process for the unit to see if any component or design changes have been made.

8) Review the Factory Acceptance Tests (FAT), Site Acceptance Tests (SAT), and commissioning tests conducted, along with the history of the process (e.g., similar products manufactured using comparable equipment).

9) Determine if other machines of a similar type are in use to see if that knowledge can be used in the development of the protocol.

10) Inquire if there are any existing protocols or products similar to the one to be manufactured in the unit, which currently utilize similar equipment.

11) Thoroughly review current regulatory guidelines and current warning letters. Understanding the FDA or other regulatory agencies’ expectations is essential for crafting a clear and concise protocol.

Preparing the Protocol

1. Only qualify critical systems and critical components: Perform a component impact assessment to develop a critical components list and only qualify those critical systems and those components within the system that are essential for the unit’s operation or have direct impact or contact with the product. Non-essential elements, such as lightning or steam supply, etc do not require qualification.
2. Prepare protocol: Prepare the protocol with predetermined acceptance criteria. You need to have a planned approach to qualification, ensuring that all testing aligns with user requirements specifications (URS) rather than design specifications alone.
3. Format:  Protocols need to have a specific defined structure or format. However, this format is not as important as its content. Once a format has been established for a company or consultancy, try to maintain this format for future protocols.

Step 2: Execute an IQ OQ or PQ protocol

This is where you take the documents (paper or electronic) out on-site and execute each of the IQ OQ or PQ protocols. You’ll be leaving your desk and going out onto the factory floor with the checklist in hand. You’ll then use it to test and confirm everything is correctly installed, properly configured, and works as intended under load.

Pre-execution checklist

1. Review the protocol and confirm what is to be tested and how it is to be performed.
2. Make sure you have the current (correct) version of the protocols that are to be executed and review them before starting the execution.
3. Check that the protocols have been fully approved (by QA, Engineering, Maintenance, Calibration, etc) before starting the execution paying attention to the operational parameters and environmental conditions.
4. Check that the equipment is ready and available for the current protocol execution (e.g. it may have been approved for use in or for another product or situation).
5. Review safety procedures.
6. Notify owners of scheduled validation work.
7. Collect necessary test instruments, check they’re all calibrated and that their calibration certificates are available for attachment to the protocol.
8. Notify any specialists you need to assist with testing (e.g. operators, electricians, fitters).
9. Obtain relevant SOPs.
10. Make a COPY of the protocol(s) to be executed and ensure that all pages are accounted for.

Completing the execution

1. Do not make assumptions.
2. Make sure that all piping is clearly identified and tagged.
3. Make sure that utility connections are correct and tagged.
4. All data/entries should be made on the protocol page. Additional pages may be added if necessary, with a unique number.
5. All entries should be neat and legible to others.
6. Don’t leave any blank lines or spaces.
7. Make sure to follow Good Documentation Practices.
8. The IQ protocol must be signed before the OQ can be signed.
9. The OQ protocol must be signed before the PQ can be signed.
10. All deviations must be closed before signing any protocol as complete.
11. All data are entered and either initialled or signed and dated at the point of execution. -No pre or post-dating is allowed.

Always Remember!

1. The goal is to make safe medicines at an affordable cost – you must balance these objectives. There can be a tendency, especially amongst novice C&Q technicians and engineers to qualify all components in a system. However, the qualification process is enormously time-consuming and expensive so this approach drives up the cost of qualifying and validating the project and subsequently the final price of medicine way higher than necessary (which makes it unaffordable to less well-off patients). The solution is to use system impact assessments, component impact assessments and risk management tools in a scientifically robust manner to support your decisions about what to validate to avoid over-qualifying.
2. Use commissioning data wherever possible to reduce testing duplication. The quality assurance department will need to approve.
3. There is no single right answer or a “perfect” approach to validating a project. In fact, there are always multiple right answers and approaches. The key point is that you must be able to explain your rationale to an FDA or EMA auditor or supervisor. As long as your rationale is sound and logical so that even if someone disagrees with you, they can understand the decision, you won’t be penalised (even if you are asked to change it).