Is NEN 3140 mandatory?

Short answer: the standard itself is not mandatory, but the result is. The Arbobesluit (Dutch Working Conditions Decree) requires you to keep electrical installations safe and to have work equipment tested. NEN 3140 is the common way to demonstrate that. The table below shows what this means in each situation. For the general explanation of the standard, see What is NEN 3140?

The law nowhere mentions NEN 3140 by name. The obligation lies in the result: safe installations and tested equipment. You can also demonstrate that result in another way, although NEN 3140 is the standard route.

What does the Arbobesluit say?

The articles below are in the Arbobesluit. The summary follows the text on wetten.overheid.nl. For a legal decision, always read the current article text yourself.

Article	Title in the Arbobesluit	What it means for you
3.4	Electrical installations	The installation is designed, installed and maintained safely, and there are clear, up-to-date diagrams
3.5	Electrotechnical, operating and other work on or near an electrical installation	Only expert, adequately instructed and authorised employees do dangerous electrical work. In principle, you work with the power switched off
7.4a	Testing	Work equipment that can deteriorate is tested as often as necessary. This also applies to electrical tools. The proof must be present at the workplace

Article 3.4 is the reason you have a NEN 3140 inspection carried out. Article 3.5 is the reason you appoint people as VP or VOP. Article 7.4a is the reason you have your tools tested.

What applies in each situation?

Situation	What the law requires	Common approach
Fixed installation in your premises	Safe installation (article 3.4)	Periodic NEN 3140 inspection, possibly a Scope 8 inspection
Electrical tools and appliances	Periodic testing (article 7.4a)	Testing according to NEN 3140, with instructions for the tester
Fire risk and insurance	Not in the law, but the insurer can require it	A Scope 10 inspection
Client or tender	Agreements in the contract	An inspection the client accepts, often a SCIOS scope

The difference between the first two rows and the last two matters. An insurer or client can require something that the law does not mention. That is a contractual agreement, not a legal obligation.

Example: a construction company with an office and workshop

This is a fictional example. A construction company rents a workshop with its own distribution board and has fifteen pieces of electrical tools. The employer must keep the fixed installation safe and have the tools tested. That follows from the law. The employer chooses NEN 3140: the installation manager has the installation inspected, and the tools are tested according to the standard.

The fire insurer also asks for a Scope 10 inspection. That is not a legal obligation, but it is a requirement of the insurer.

Common misconception

Many people think: “NEN 3140 is mandatory, so I need a certificate.” Both parts are wrong. The standard is not a law, and there is no certificate for the standard. See NEN 3140 certificate: does it exist?.

A second misconception: “I have no staff, so the law does not apply to me.” The obligations in the Arbobesluit apply to employers. If you truly work alone, without staff or hired labour, the question is whether the law counts you as an employer. Ask the Nederlandse Arbeidsinspectie (Netherlands Labour Authority) about that. The text of the law is on wetten.overheid.nl .

What the inspector wants to see

An installation manager who is demonstrably appointed.
An inspection of the fixed installation, with a diagram and a report.
Testing of tools, with a register.
Instructions for people who work on installations.

These four items also appear on the NEN 3140 checklist.

Frequently asked questions

Does NEN 3140 also apply to an older installation?

The duty to keep an installation safe applies to every installation in use, regardless of when it was built. Different rules apply to the installation of a new or modified installation. Read about those at NEN 1010 versus NEN 3140.

What happens if I do not arrange it?

The Nederlandse Arbeidsinspectie can issue a warning or a fine. The amount depends on the violation.

Is a NEN 3140 inspection the same as a test?

No. An inspection looks at the fixed installation. A test looks at loose appliances and tools. Both belong to NEN 3140, but they are not the same. See NEN 3140 inspection.

Four steps to determine what applies to you

List all electrical installations and appliances your company uses. Think of the fixed installation, the tools, the machines and the charging points.
Ask your insurer which inspections they require. This is an agreement in your policy, not a legal obligation.
Ask your largest clients whether they require a specific inspection in their purchasing conditions.
Record the outcome in your risk inventory and evaluation (RI&E), so you can later show why you made your choices.

With these four steps, you know which inspections the law requires and which you need because of contracts and insurance. These two are often confused.

What if you outsource the inspection?

Outsourcing the inspection does not change your own responsibility. The employer remains responsible for the safety of the installation. The inspection company provides the evidence. You decide what to do with the findings.

Therefore, put in the contract what the company delivers: the report, the scope and the re-inspection. Keep the report in your file, so that an auditor or inspector can see it.

Do I have to have an inspection every year?

The law does not set a fixed period for the fixed installation. You determine that period based on risk, and you record it in your schedule. See NEN 3140 inspection for how this works in practice. For tools, the Arboportaal mentions once a year as the safe minimum.

Is an inspection of a rented property my responsibility?

As an employer who has people working there, you are generally responsible for the safety of the work yourself. Record in your lease who manages the installation and who bears the costs.