GB 50222-2017 第2.0.4条
| | **Class B1 material**: refers to materials that are difficult to ignite and not prone to spread when exposed to open flame or high temperature in air, and that self-extinguish once the ignition source is removed, such as flame-retardant treated wood, PVC sheet flooring, etc. Wall and floor finishes in hotel guest rooms are typically required to be Class B1 or above. |