1/00 |
Ventilation of mines or tunnels; Distribution of ventilating currents (ventilating rooms or spaces in general F24F) |
1/02 |
Ventilation of mines or tunnels; Distribution of ventilating currents (ventilating rooms or spaces in general F24F) Test models (analogue computers therefor G06G 7/5) |
1/04 |
Ventilation of mines or tunnels; Distribution of ventilating currents (ventilating rooms or spaces in general F24F) Air ducts (suspension devices E21F 17/02) |
1/06 |
Ventilation of mines or tunnels; Distribution of ventilating currents (ventilating rooms or spaces in general F24F) Air ducts (suspension devices E21F 17/02) Duct connections (tube connections in general F16L) |
1/08 |
Ventilation of mines or tunnels; Distribution of ventilating currents (ventilating rooms or spaces in general F24F) Ventilation arrangements in connection with air ducts, e.g. arrangements for mounting ventilators (ventilators per seF04D) |