Indoor Air Quality Assessment Based on Human Physiology - Part 2. Limits

M V Jokl

doi:10.14311/494

Abstract

In order to evaluate indoor air quality in practice it is necessary to establish limits, or more exactly, tolerable ranges for unadapted and adapted persons. The optimal value overwhelmingly corresponds to PD 20 %. A better value of PD 10 % could be prescribed for asthmatics and for persons with increased requirements, i.e. those allergic to the environment and operators in airport control towers and atomic power stations. A worse value PD 30 % could be accepted as an admissible value. These values differ for unadapted and adapted persons (as introduced by BSR/ASHRAE 62-1989 R). The long-term tolerable value is the end of SBS range (for CO2 it is based on USSR space research, for TVOC on Molhave). The short-term tolerable value is the beginning of the toxic range (for CO2 it is taken from British Guidance Note EH 40/90; for TVOC from Molhave).

Highlights

The increasing requirements for indoor air quality in buildings need more exact criteria in order to ascertain the real condition of the environment and to allow better optimization of its level, to remove “sick building” symptoms, i.e. to get the real comfort within a building
New decibel units for odor component representing indoor air quality in majority locations have been proposed: decicarbdiox dCd and decitvoc dTv – see Part 1 of this paper. Equations of these new units have been proved by application of a) experimental relationships between odor intensity and odor concentrations of CO2 and TVOC, b) individually measured CO2 and TVOC levels – from these new decibel units can be calculated and their values compared with decibel units of noise easured in the same locations
Optimal (PD = 10 %) and admissible (PD = 20 %) value for asthmatics could be for unadapted persons: 85 mg×m-3, 12 dTv (PD = 10 %) and 200 mg×m-3, 30 dTv (PD = 20 %) and for adapted persons: 250 mg×m-3, 35 dTv (PD = 10 %) and 580 mg×m-3, 53 dTv (PD = 20 %). Besides asthmatics these values are recommended for people with increased requirements: those allergic to the environment or those having responsible positions – operators in airport control towers and power stations, especially atomic power stations

Summary

Introduction

The increasing requirements for indoor air quality in buildings need more exact criteria in order to ascertain the real condition of the environment and to allow better optimization of its level, to remove “sick building” symptoms, i.e. to get the real comfort within a building. Human physiology research makes evident that the Weber-Fechner law applies to noise perception, and to the perception of other environmental components Based on this fact, new decibel units for odor component representing indoor air quality in majority locations have been proposed: decicarbdiox dCd (for carbon dioxide CO2) and decitvoc dTv (for total volatile organic compound TVOC) – see Part 1 of this paper. New decibel units for odor component representing indoor air quality in majority locations have been proposed: decicarbdiox dCd (for carbon dioxide CO2) and decitvoc dTv (for total volatile organic compound TVOC) – see Part 1 of this paper Equations of these new units have been proved by application of a) experimental relationships between odor intensity (representing odor perception by the human body) and odor concentrations of CO2 and TVOC, b) individually measured CO2 and TVOC levels (concentrations) – from these new decibel units can be calculated and their values compared with decibel units of noise easured in the same locations. To be able to evaluate the indoor air quality in practice, we need to establish limits or, more exactly, admissible and tolerable ranges for both unadapted and adapted persons (P)

Carbon dioxide

USSR space research

Physical exercise

Total volatile organic compounds

Conclusions