Is ventilation the answer to indoor air quality control in buildings? Do we need performance-based approaches?
Indoor exposure to contaminants should be minimised to avoid adverse health and comfort effects. Experience shows that this qualitative statement is difficult to translate into measurable terms, such as performance indicators or metrics, which can be used as a basis for defining and assessing requirements in regulations and standards while holistically reflecting indoor air quality (IAQ). The simplest and most commonly used approaches rely on ventilation airflow rates determined by experts or codes. These approaches have fundamental shortcomings in practice for systems that do not have steady contaminant sources or do not provide a constant airflow rate, such as natural, hybrid, or demand-controlled ventilation (DCV). More sophisticated approaches can be based on health damage, pollutant exposures, or perceived air quality but they generally entail a number of assumptions about the pollutants of concern and occupant scenarios. Such methods could lead to useful metrics. However, as of today, there is no clear set of metrics that can be used to assess the overall ventilation performance of a building with regard to its indoor air quality, or used in standards or regulations.
This workshop, organised by the Air Infiltration and Ventilation Centre (AIVC) aims to identify the pros and cons of performance-based approaches and metrics that can be considered to assess the IAQ performance of ventilation systems, as well as to draft guidelines for their use in standards and regulations.
The workshop addresses IAQ performance for all building types and ages, with all types of ventilation system (natural, mechanical, hybrid systems). It does not cover the relevance of the associated metrics in terms of health, comfort or building damage, but looks at their relevance for comparing system performance or strategies in terms of IAQ. It focusses on performance-based approaches, such as those that focus on the performance to achieve rather than on the techniques or systems to be implemented.
Topics addressed in presentations and discussions:
- Factors that should influence IAQ assessment
- Is CO2 an indoor pollutant?
- The potential for, and limits of, CO2 based indices, humidity or moisture, health damage, perceived air quality, air mixing behaviour, and pollutant distribution within a space
- The potential for, and limits of, combined indices
- Definition and use of rating methods for smart ventilation, DCVs, natural ventilation, etc. (equivalent ventilation principle)
- Barriers to performance-based standards (showing evidence of compliance, accounting for sources, sensors and controls, time-activity patterns)
Keynote presentations will focus on the specifications and needs for performance-based approaches and associated IAQ metrics for building ventilation, which consider pollutants and sources of concern. The regular session presentations will review IAQ indices, analyse their pros and cons, and suggest improvements where necessary.
The attendees at this workshop are expected to participate, either through presentation, or in active discussions during each session. Target attendees are experts, professionals, or scientists researching ventilation or IAQ issues related to existing or potentially new IAQ performance approaches, such as metrics.
For additional information please download the programme and visit the AIVC's website at the link provided below.