Upcoming seminar

Visitors and occupants: examples of recommended ventilation rates for non-residential buildings!
August 19, 2015

Visitors and occupants: examples of recommended ventilation rates for non-residential buildings!

The first international standard that dealt with all indoor environmental parameters (thermal comfort, air quality, lighting and acoustic) was published in 2007 as EN15251. This standard prescribed input parameters for design and assessment of energy performance of buildings and was a part of the set of standards developed to support the implementation of the Energy Performance of Buildings Directive in Europe. The standard has now been revised and issued for public comments with a new number: prEN16798-1. Besides the standard, a Technical Report 16798-2 is also being developed to support and explain the standard in more details.

One of the most interesting criteria is based on an occupant and a visitor ventilation rates. An occupant as a possible design for adapted persons, i.e. persons that have occupied the space for more than 15 minutes and then adapted to the odour level of bioeffluent from the occupants. This may be relevant for spaces like conference rooms and auditorium, where people enter at the same time. The odour level will increase (perceived air quality decrease); but at the same time the occupants adapt to the odour level in the space and the lower ventilation and level of perceived air quality acceptable. This is as example the basis for the minimum ventilation rates given in ASHRAE standard 62.1. In the present standard prEN16798-1 the criteria of a total ventilation of minimum 4 l/s person must be fulfilled. It can be seen in Table 5 that only in a few cases the criteria of 4 l/s person will be used and only for category 4. On the other hand if the ventilation rate is designed for adapted occupants the criteria of minimum 4 l/s person is used in all cases except for Category I. The values in italics indicate situations where the calculated ventilation rate is lower than the minimum value of 4 l/s per person required for health.

visitor vs occupant table

This is an excerpt from the article on “Indoor environmental input parameters for the design and assessment of energy performance of buildings” by Bjarne W. Olesen published in the REHVA Journal 1/2015.