ISO 50001 auditor: what they do during the audit and what to expect
An ISO 50001 auditor assesses whether your energy management system (EnMS) meets ISO 50001:2018 and whether it works in practice. The auditor works for or on behalf of a certification body accredited by the Dutch Accreditation Council (Raad voor Accreditatie, RvA) , and is independent of your organisation. If you understand the role, you prepare better. The full course of the audit is on the audit page. To check the certificate afterwards, read verifying a certificate.
The auditor checks your system. They are not a consultant. The auditor may record a nonconformity, but does not decide how you resolve it. A consultant can help you prepare, but cannot be your auditor.
What does the auditor do exactly?
The auditor’s task is limited and clearly defined. They test your system against the requirements of ISO 50001 and the rules of the certification body. They do not judge your energy savings as such, and they do not decide which measures you take. They do assess whether you establish your savings and baseline in a way that can be verified.
In practice the auditor does three things:
- Reviews documentation: is the energy management system fully described, and is the scope correct?
- Tests implementation: does the system work in practice, and is there measuring, analysis and action?
- Identifies nonconformities: where does the system fail to meet the requirements, and how serious is it?
What does the auditor do in phase 1 and phase 2?
The certification audit consists of two phases. In phase 1 the auditor reads your documents and checks whether you are ready for phase 2. In phase 2 the auditor comes on site to see whether the system works. The auditor then discusses the findings (observation, minor or major nonconformity), and the certification body decides. What happens exactly in each phase, how long it takes and what the outcomes mean is on the audit page.
Here the focus is the auditor’s own role. A few examples of questions the auditor asks:
- To top management: “What resources have you allocated to this year’s energy objectives?”
- To the energy manager: “Why is the compressed air system a significant energy aspect and the lighting not?”
- To an operator: “What do you do if this device keeps running outside production hours?”
Example of an audit day
The table below is a fictional example of a phase 2 audit at a manufacturing company with two sites. It shows how the auditor divides their time.
| Time | Topic | What the auditor checks |
|---|---|---|
| 09:00 | Opening | Scope, plan and the auditor’s authority |
| 09:30 | Top management | Energy policy, leadership and allocation of resources |
| 10:30 | Energy manager | SEUs, energy review, baseline and EnPIs |
| 13:00 | Site A, production | Meters, measurement data and how the installation works |
| 14:30 | Site B, maintenance | Operational control and maintenance schedules |
| 15:45 | Closing | Provisional findings and next steps |
Note: this is an illustration. The exact schedule differs by organisation and by certification body.
What competence can you expect from an ISO 50001 auditor?
The requirements for the certification body and the auditor are not in ISO 50001 itself, but in ISO 50003 (for energy management systems) and in the general accreditation standard ISO/IEC 17021-1. The certification body must demonstrate that the auditor has knowledge of energy management and of auditing. This is not a fixed diploma, but a demonstrable combination of education, experience and training. ISO 50003 also determines how many audit days a certification body must plan for your organisation. See energy management standards.
When choosing a certification body, you can ask the following:
- Does the auditor have experience in the sector you work in?
- Does the auditor know energy carriers such as electricity, natural gas or fuel?
- Can the auditor assess the energy baseline and the normalisation of your EnPIs?
- Is the auditor independent, and have they played no part in implementing the system at your organisation?
These questions are about competence. You can read more about choosing the certification body itself under choosing a certification body.
Why can the auditor not have helped you?
A certification body must be impartial. According to ISO/IEC 17021-1, a certification body may not provide consultancy services that compromise its independence. An auditor who advised you in the past two years may not audit you. For example: consultancy firm X helps you set up the system. Then the certification body must send an auditor who has never worked with you or with firm X.
Common mistakes with the ISO 50001 auditor
Treating the auditor as a consultant. The auditor assesses and does not advise. Asking about the intent of a requirement is fine. An extended advisory discussion takes time and causes confusion.
Preparing documentation only on the day. The auditor reads the documents in phase 1. Make sure they are ready and up to date before the auditor arrives.
Not preparing staff. Everyone who has a task in the energy management system must be able to explain what they do and why. A fine document does not help if the shop floor does not know it.
Defending nonconformities instead of resolving them. A nonconformity is a control point. Respond with a cause, an action and a deadline.
Not keeping a file. The auditor looks for evidence. Keep measurement data, management review minutes and the action plan together.
What this means for choosing a certification body
When you request a certification quote, do not only ask about the price. Also look at the auditor’s experience in your sector and at the working method of the certification body. A fair and independent assessment is worth more than a quick audit. Read comparing quotes for the questions to ask with every quote, and the costs and timeline for what an audit costs.
Frequently asked questions
Can my own consultant be the auditor? No. The auditor must be independent of the organisation and of the implementation. A consultant who set up the system therefore cannot carry out the certification audit themselves.
Can I choose the auditor myself? You choose the certification body. The certification body assigns the auditor. If you have a clear reason for objection, such as a conflict of interest, discuss it with the certification body in advance.
What if the auditor records a nonconformity that I do not understand? Ask for an explanation and have it given to you in writing. You respond within the stated deadline with a cause and an action.
Does the auditor come back every year? Yes. In the years between certification and recertification, a surveillance audit takes place every year. After three years the audit is complete again. The self-check you carry out yourself is covered on the page about the internal audit.
More information
- The audit process for ISO 50001: phases, outcomes and preparation
- Internal audit (clause 9.2): the check you carry out yourself
- Verifying an ISO 50001 certificate: how to check a certificate
Sources
- ISO 50001:2018 : the standard on which the audit is based
- Dutch Accreditation Council (RvA), all accredited bodies : accreditation of certification bodies