A brattice is a partition used in mining. It is built between columns of a sub-surface mine to direct air for ventilation. Where the mine is sunk at the base of a single shaft, the shaft is divided into two parts by a wooden or metal brattice. Air is delivered down one side of the shaft and exhausted upwards through the other.
Depending on the type of mine and how the operation is run, brattices can be permanent (concrete or wood) or temporary (cloth). Temporary installations are also called curtains.
Failure of the brattice due to damage in an accident and the resultant lack of ventilation was a major factor in 204 deaths of the Hartley Colliery Disaster. After this, mine regulations in the United Kingdom were changed so that at least two independent shafts were required for down-cast and up-cast ventilation.
Brattice, from the French bretèche, originally referred to part of a castle. This was a small wooden structure, sometimes temporary, that projected out beyond the main part of a castle wall, so as to give flanking fire along that wall whilst still offering some degree of protection. See hoarding.