United Company RUSAL is the world's largest producer of aluminium and alumina. The Boguchany Smelter Complex is a subsidiary of this company and produces 750,000 tonnes of aluminium per year.

Technical requirements
There are extreme conditions at the Boguchany Smelter Complex. Therefore the Colt Systems have to operate in this enviroment:

• The temperature varies from -47°C to +25 °C
• The snow load in winter time can be as much as 1000N/m²
• The wind speed can be as high as 45 m/s.
• Defence against 75 mm/h of rain may be required.
• A ventilation flow rate of 100,000,000 m³/h may be required.

Colt carried out a survey and technical calculations, and proposed a scheme of Labyrinth gravity ventilators. Each of the four potrooms with a length of 1,200m will be equipped with a 7m wide Labyrinth unit.

This type of Labyrinth has been especially developed to meet the requirements of smelters. It is made of light weight aluminium, it has high performance, it is corrosion resistant and is maintenance free, and atmospheric dust does not affect its capacity to operate.