De or het brandwerendheid?

The correct Dutch article is:

de brandwerendheid

Rule Words ending in -heid: almost always de. See the rule
Meaning (Dutch) het brandwerend zijn

How to use brandwerendheid

the brandwerendheidde brandwerendheid
this brandwerendheiddeze brandwerendheid
that brandwerendheiddie brandwerendheid
our brandwerendheidonze brandwerendheid
your brandwerendheidjouw brandwerendheid
every brandwerendheidelke brandwerendheid
which brandwerendheid?welke brandwerendheid?
a big brandwerendheid / the big brandwerendheideen grote brandwerendheid, de grote brandwerendheid

Meaning, plural, diminutive, pronunciation and translations: WikiWoordenboek (Dutch Wiktionary) (CC BY-SA 4.0). Example sentences: Tatoeba (CC BY 2.0 FR).