Outdoor temperature and indoor thermal comfort - raising the precision of the relationship for the 1998 ASHRAE database of field studies.

Relations between indoor neutral temperatures and outdoor temperatures are currently proposed as an "adaptive standard" to supplement ASHRAE Standard 55-1992. They rest on the 1998 ASHRAE database. Humphreys and Nicol drew attention to the depression of the regression coefficient by measurement and formulaic error in thermal comfort indices. This paper applies their suggested correction, and improves the precision of the relations. Comparison is made with similar relations from earlier data. The relation for unheated, naturally ventilated buildings has remained unchanged.

Error analysis of measurement and control techniques of outside air intake rates in VAV systems.

This paper provides a theoretical error analysis of common airflow measurement and control techniques to maintain minimum outside air intake rates in variable air volume (VA V) systems. The results of the error analysis indicate that control strategies using direct airflow measurement from either an averaging Pitot-tube array or an electronic thermal anemometry provided the best ventilation control.

Glass fiber emissions from HVAC ductwork: a review of the literature.

Recent concerns have been expressed with regard to emissions of glass fibers from heating, ventilation, and air conditioning (HV AC) systems. In this literature review, over 350 citations were found, of which 10 reported original measurements of glass fiber concentrations associated with the presence of fibrous glass duct lining or duct board, and two yielded sufficient data from which emission rates could be calculated.

Reduction of sensory pollution by air filters: effect of treatment to inhibit microbial growth.

Ventilation systems may in some cases be a major contributor to indoor air pollution. Several studies have shown that the pollution mainly originates from the filters. Microbial growth in the filters is seen as a cause for this pollution. The sensory pollution from a standard glass fiber filter and a glass fiber filter treated to inhibit microbial growth (both EU7) were compared. No clear pattern was found in the influence of the filters on the sensory air quality. The differences between the two tested filters were not significant.

The influence of service life, filter medium, air temperature and relative humidity on the growth of microorganisms on air filters in HVAC systems.

Concerning artificial ventilation of interiors, microbial processes on air filters are assumed to cause pollution of the supply air with possible damage to the exposed persons' health. Therefore, the reaction of microorganisms on air filters was analysed in this project. The analysis focused on the influence of air temperature, relative air humidity, the filter medium and service life as determinants for microbial growth on air filters. The experiments showed that the parameters air temperature, filter medium and service life had no significant influence on microbial growth.

Ventilation and air-conditioning systems - investigations to the odour and possibilities of cleaning.

For many years there has been an increasing rate of complaints on the air quality in nonindustrial buildings. The occupants suffer from many diseases especially problems of breathing. Besides other reasons the air-conditioning systems themselves pollute the indoor air because dust, aerosols and other substances deposit inside the system. Therefore an airconditioning system, which has been operating 26 years was investigated. The aim was to find the main pollution sources of the system and possibilities to eliminate them.

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