Ventilation of ETA 3 rooms in buildings

The European standard prEN 13779 - Ventilation for non-residential buildings [1] distinguishes four categories of decreasing air quality, ETA 1 to 4, for rooms in buildings. We tested the separation effectiveness between a special designed smoking porch, which is a typical ETA 3 room, and the adjoining lobby at Delft University of Technology. The ventilation effectiveness in the smoking porch, which was heated and ventilated by a pseudodisplacement ventilation system, was measured as well.
For the ETS measurements we used an innovative Ultra Fine Particle sensor, newly developed
by Philips Research. The measurements were carried out at four different ventilation rates, ranging from 4.8 to 19.2 dm3/s.m2, with a difference of -1.9 dm3/s.m2 between supply and exhaust. In each test approximately 40 cigarettes were burned. The measured separation effectiveness was 0.97 in all tests, which is higher than is found in literature on this subject.
The ventilation effectiveness, expressed in the Contaminant Removal Effectiveness, is low, which can be attributed to the cold downdraught along the outer facade, which mixes with the supply air. In order to realize a high separation effectiveness, a ventilation rate of 4.8 dm3/s.m2 with a difference of -1.9 dm3/s.m2 between supply and exhaust is sufficient. In order to obtain a passable air quality in the smoking porch the ventilation rate should be 5-6 times higher