Housrey special type fire door core board (perlite) Mainly applied to wooden fire door, steel fire door in the fire fill material;

防火门专用豪仕莱特芯板（珍珠岩）主要适用于木质防火门、钢质防火门的防火填充材料；

youdao

Immediately to my right is the wooden door, and behind it the steel barred door, that leads down to the cells.

BBC: Oscar Pistorius: Drama of the courtroom