Wide openings that do not justify two full leaves: one wide active leaf, one narrow passive panel, one shared frame. The mother-son layout is a certified construction on our GB certificates — not a site improvisation.
Specifications
| Configuration | Mother-son (sub-master): wide active leaf + narrow passive panel in one frame |
|---|---|
| Fire performance | 0.5 / 1.0 / 1.5 h — GB 12955-2008 steel and steel-wood composite insulated fire door families |
| Certified mother-son models — steel | GFM-1523-dk5 Class B mother-son, decorative face — Z2018081806009538 (also covers GFM-1223) · GFM-1223-dk5 Class A mother-son, pressed face with viewer — Z2016081806004335 · GFM-1523 mother-son under the Class B pair certificate Z2015081806004972 |
| Certified mother-son models — steel-wood | GMFM-1523 Class B — Z2015081806004969 · GMFM-1523 / 1223 Class A — Z2016081806004334 |
| Double-leaf families | GFM-2123-dk5 Class A — Z2018081806009545 · GFM-2123-bdk5 / dk5 Class B — Z2015081806004972 |
| North-American program | Current Intertek listings cover single-leaf steel constructions — 90 min, single swing 1120 × 2355 mm (ATM 91995). Mother-son units ship under the GB certificate program. |
| Vision panel | Engineered per opening; certified glazing envelope reference: max 330 × 330 mm, min bite 12.5 mm (Listing 92609) |
| Certificate validity | CCCF certificates active into 2029 |
Evidence & documentation
- Intertek test report 250612025SHF-004 — 90-minute steel fire door + frame (30 pages) · View PDF
- Authorization to Mark 91995 — single-leaf steel fire door, 90 min · View PDF
- Full certification wall — reports, authorizations and listings · certifications
Every quote ships with the matching test report, listing extract and hardware schedule. Request a project quote.