On the safe side with MUF adhesives / by Mr. Günther Jauk, Holzkurier

On the safe side with MUF adhesives

New formaldehyde limits are not a problem for MUF adhesives

From August 6, stricter formaldehyde limits will apply in the EU for wood-based materials and furniture.
Even under extreme test conditions—such as significantly increased adhesive spread, maximum loading factor, and minimal hardener content—Dynea’s Prefere low-emission adhesives easily meet the new requirements. In direct comparison, they show identical properties to 1K-PUR adhesives.

Günther Jauk – Holzkurier

“Is it true that MUF adhesives will no longer be allowed in the EU from August 6?” – Dynea General Manager Sales Franz Windisch and Dynea Technical Service Manager Felix Drexler are regularly confronted with this and similar questions.

Although the formaldehyde issue with MUF adhesives has been technically resolved, there is still a need for clarification in practice. With the announced tightening of limits, the topic has once again come more strongly into focus in recent months.

Specifically, the EU will halve the formaldehyde limit for wood-based materials and furniture from the current 0.1 ppm to 0.05 ppm per cubic meter of indoor air starting August 6, 2026. For other products, the limit will decrease to 0.064 ppm (Commission Regulation EU 2023/1464 of July 14, 2023).

It is still unclear which limit will apply to solid wood products in the future. However, the loading factor for chamber testing according to EN 717-1 has now been clarified. For glued laminated timber according to EN 14080, it will remain at 0.3 m²/m³.

“To cover all requirements, we generally use a loading factor of 0.5 m²/m³,” explains Drexler, adding:

“We also deliberately choose demanding test parameters. We test with minimal hardener content and an adhesive application that is about 60% above the usual amount. This worst-case scenario gives us and our customers additional security.”

No measurable difference compared to PUR

For reliable comparative values, Dynea tested two MUF low-emission adhesives—Prefere 4570 and Prefere 4571—together with an external testing institute, as well as glulam samples bonded with a standard PUR adhesive.

“Despite the deliberately stricter test conditions for the MUF samples, there was practically no difference compared to the PUR-bonded test specimens,” summarizes Drexler.

The chamber tests could be completed after the shortest possible duration of four days, as no measurable change in concentration occurred. According to Drexler, the low formaldehyde levels in the PUR samples are attributable to the wood itself.

Low-emission systems gaining importance

“With measurement values of around 0.01 ppm, the new EU regulation is practically irrelevant for us and our customers,” concludes Windisch.

Already today, more than 50% of Dynea customers in the structural sector use low-emission adhesives. At the same time, conventional MUF systems from the company also fall well below the new limits.

With a free formaldehyde content of less than 0.1%, the MUF adhesives Prefere 4570 and Prefere 4571 do not require labeling and, unlike many other adhesive systems, do not carry hazard pictograms.

In addition to common softwood species such as spruce, fir, pine, larch, and Douglas fir, these adhesives are also suitable for bonding birch.

More on the topic

Formaldehyde is one of the most extensively studied chemicals worldwide.
More information can be found at: www.formacare.eu

HOLZKURIER 20 – May 15, 2026