Items that Require Vetting and Analysis
The sections noting air handling requirements for both high and medium risk occupations reference ASHRAE standards that have not yet been adopted as part of VUSBC (ASHRAE 2017 and 2019) as they were released just last November. It is doubtful therefore that even the newest facilities recently brought online would comply with these design standards.
The revised 2019 edition of the standard includes significant changes, including:
- New informative tables of ventilation rates per unit area for checking new and existing buildings ventilation calculations
- Simplified version of the Ventilation Rate Procedure improving calculations for system ventilation efficiency and zone air distribution effectiveness
- Modified Natural Ventilation Procedure calculation methodology
- Revised scope to specifically identify occupancies previously not covered
- Natural ventilation now requires considering the quality of the outdoor air and interaction of the outdoor air with mechanically cooled spaces.
- Humidity control requirements are now expressed as dew point and not as relative humidity.
In addition, the maintenance code requires property owners to maintain the standards in place as of the date of issuance of their respective building permits. Even if equipment is replaced it is “like for like” so that one does not have to redesign and replace the entire HVAC system just because a 15-year old condensing unit reached the end of its useful life. These regulations, as proposed, present fundamental changes to the maintenance code, which is part of the VUSBC family.