During our measurement we encounter situation which is not clearly explained in the Standard. There is a chimney with gravitational ventilation passing through whole building. It is made with several canals,
each of them has surface less than 0,1 square meters, however area of whole chimney is about 2 square meters (wall with shafts is 0.6 meter wide and is surrounded by Occupant Area).

It is not clear if we should assume that several canals which are fixed element of building structure should be
interpreted as a installation shaft, therefore included in Major Vertical Penetration. “major vertical penetration – a floor opening in excess of 1 square foot (0.1 square meter) that serves vertical
building systems or vertical occupant circulation functions. Discussion: Major vertical penetrations include stairs, elevators shafts, flues, pipe shafts, vertical ventilation ducts and their enclosing walls. Major vertical penetrations exclude voids (a significant change from the predecessor standard). See discussion under Section 6.2 of Measurement Concepts.”

On the other hand Standards show example of set of vertical pipes each of them less than 0,1 square meters,
that are included in Floor Service Area.