What does a CO inspection cost? The cost of CO certification for installation companies

What this article covers

In practice, "CO inspection" is used for two things: the technical check your technician carries out on site (see CO inspection: checklist and what needs to be on your work order), and the certification track your company and technicians need in order to be legally allowed to carry out that work on gas-fired combustion installations. This article covers the second question: what does it cost to become CO-certified as an installation company, via BRL 6000-25 or BRL K25000?

Since 1 April 2023 the rule is: only certified installation companies and technicians with a valid Bewijs van Vakmanschap CO may still carry out work on gas-fired combustion appliances up to 100 kW (installation, repair, maintenance, and work on combustion air supply and flue gas discharge systems). See also What is the Gasketelwet?.

Two routes, two cost pictures

There are two recognised certification routes:

• BRL 6000-25 — the regular scope area within the BRL 6000 series, certified via InstallQ with a certifying body (CI) such as Kiwa, DEKRA, Bureau Veritas, Normec Certification or SKG-IKOB. Intended for installation companies of any size.
• BRL K25000 — a more compact variant developed by Kiwa, explicitly positioned as a cost-effective alternative for smaller installation companies and sole traders. Kiwa carries out audits partly remotely, which makes the track shorter and cheaper. We haven't been able to find a hard FTE limit for admission in official sources — check this with Kiwa for your own situation.

The choice between the two largely determines your cost picture.

The exam: Bewijs van Vakmanschap CO

Every technician who carries out CO work personally needs a Bewijs van Vakmanschap CO (both a theory and a practical assessment). Background on this is available in CO-person certificate: the professional-competence proof for gas work.

According to InstallQ's own step-by-step plan, the exam costs are approximately €500 for the combined theory and practical assessment, taken via a recognised exam location at vakmanschapco.nl.

Note: this is the bare exam rate. Private training providers who offer the course and exam as a package often charge considerably more — with one provider we saw, for example, training costs of €630 (incl. theory exam, VAT-exempt) plus a practical exam of €495 (single profile) up to €695 (combined profile). So always compare what is and isn't included in the price: some providers charge separate resit fees, others don't.

Annual costs at InstallQ (BRL 6000-25)

For the BRL 6000 series, InstallQ publishes a fixed annual levy per certificate:

• Fixed amount for the basic BRL 6000 certificate: €216 per year
• Surcharge per Special Part (such as scope area 25, CO prevention): €80 per year
• Extra per secondary branch: €256 per year
• Reduced rate for micro-SMEs (maximum 6 FTE) with basic certificate + scope area 25 combined: €277 per year

In addition, trade literature mentions an annual contribution of around €55 to Stichting Bouwkwaliteit for certificate holders of both BRL 6000-25 and BRL K25000 — we haven't been able to verify this amount directly on an official Stichting Bouwkwaliteit page, so treat it as indicative.

The CI's audit costs: no fixed rate

This is where most of the uncertainty lies. The CI (Kiwa, DEKRA, Bureau Veritas, Normec, SKG-IKOB) itself determines the number of audit days and the hourly rate, depending on:

• the size of your company and the number of employees who need to be certified
• the complexity and breadth of the work (maintenance only, or also installation and repair)
• the number of locations
• whether you already hold an ongoing BRL 6000 certificate (in which case scope area 25 can often be added as an extension, which is cheaper than a completely new track)

No CI publishes a fixed price list for this — both Kiwa and DEKRA explicitly refer to a tailor-made quote. So request a quote from at least two CIs and compare not only the price, but also the number of audit days and whether (part of) the audit can be done remotely.

Extra cost item: the quality manual

For both routes you need a quality manual that describes how your company safeguards CO safety. You can write this yourself, have it written by a consultancy, or use a ready-made template — as an example: one provider offers a workshop-model quality manual for BRL K25000 for €795. Prices from consultancies for bespoke work vary widely; request a quote.

Why K25000 often works out cheaper

For smaller companies and sole traders, the K25000 route is generally lower in cost, for a few reasons we saw confirmed in official sources:

• Kiwa doesn't charge separate participation costs for K25000, unlike the regular BRL 6000-25 track
• the standard itself can be downloaded free of charge from Kiwa, while access to the BRL 6000-25 text via ISSO requires a subscription
• audits are partly carried out remotely, which saves audit days (and therefore costs)
• the certification track is shorter and the administrative requirements are lighter

Kiwa doesn't publish an exact total amount for K25000 — here too, the rule is: request a quote.

Cost overview at a glance

• Bewijs van Vakmanschap CO exam (per technician): approximately €500 bare, higher if training is included
• Annual InstallQ levy BRL 6000 + scope area 25: €277–€296 per year (depending on company size), plus €256 per extra location
• Annual contribution Stichting Bouwkwaliteit: indicative approximately €55 (not officially verified)
• Quality manual: write it yourself (time), ready-made template from approximately €795, or bespoke via a consultancy
• CI audit costs: no fixed rate, always request a quote from at least two CIs
• K25000 route: no separate Kiwa participation costs, free standard document, but total price only known via a quote

Recertification: cheaper than the initial application

For both the personal certificate and the company certificate, in practice recertification (after the validity period ends) is generally cheaper than an initial application, because a refresher course with a theory test is usually enough instead of a completely new theory-and-practical track. Exact amounts differ per provider and per year — request a current quote. More about the retesting system for the installation itself (as opposed to the certificate) can be found in CO inspection: why there is no fixed retesting interval laid down.

In conclusion

The hard, centrally published amounts are limited: the exam (~€500) and the InstallQ annual levy (€216–€296, or €277 for micro-SMEs) are the only figures that come directly from InstallQ itself. For audit costs at the CI and for the total price of a K25000 track, a tailor-made quote is unavoidable — the spread between companies is simply too great for a fixed price list. When requesting quotes, always compare what is included: audit days, travel time, re-inspection costs and access to the standard documentation.

See also What does a BRL 100 audit cost? Cost structure and factors and What does a leak check by an external company cost? for comparable cost analyses of other mandatory certifications and inspections in refrigeration engineering.