Defines T30, T60, T90 — the German classifications for fire doors in Sprockhövel.
A fire door is a building-authority-approved fire-resisting closure. It delays fire spread for a defined duration — 30, 60 or 90 minutes (T30, T60, T90 in German classification, EI30/EI60/EI90 by European norm). Every door we install in Sprockhövel carries an approval number and a declaration of conformity that the insurer can verify.

