A two compartment model for determining the contribution of sources, surface deposition and resuspension to air and surface dust concentration levels in occupied rooms.

A semi-empirical two-compartment constant parameter model is used to predict airborne and surface du t concentrations. The model parameters are air in- and exfiltration internal particle sources, surface deposition caused by settling. Brownian and turbulent diffusion and thermophoresis track-in of dust particle and resuspension. Model predictions are calculated for some typical scenarios, and the soiling rate of a vertical surface is calculated for a range of friction velocities and electric field strengths.

IAQ in nursing homes.

Many significant ASHRAE papers devoted to hospital ventilation have been published. In contrast, literature regarding ventilation in nursing facilities is rare. Nursing facilities are distinctly different from hospitals. This article provides some insight and guidance toward the design for such facilities.

Measurement of thermal comfort and indoor air quality aboard 43 flights on commercial airlines.

This paper reports the results of thermal comfort and indoor air quality measurements aboard aircraft from 43 flights on commercial airlines with a duration of more than 1 h. The measurements were performed continuously during the whole flight (from the departure gate to the arrival gate), and the parameters monitored were temperature, relative humidity and carbon dioxide concentration. The results were then compared with the ASHRAE Standards for the thermal comfort (ASHRAE Standard 55-92) and indoor air quality (ASHRAE Standard 62-89).

Influence of the boundary thermal conditions on the air change efficiency indexes.

The influence of a thermal heterogeneity boundary conditions on the air change efficiency (ACE) of a mechanical ventilation system in a test room was experimentally evaluated by means of the "step-down" tracer gas technique in 24 different experimental conditions. The experiments were performed under isothermal condition, varying the air supply temperature with respect to the walls and varying the surface temperature of a wall with respect to the other walls and the supply air, simulating both heating and cooling situations.

Air-change effectiveness: theory and calculation methods.

 This paper reports the development of methods for calculating a ventilation performance metric that is a measure of the airflow pattern in a room or zone of a multi-zone ventilation system. Temporal mixing theory is used as the basis for these methods. The methods are applicable to all ventilated systems that can be modeled as a set of interconnected chambers. Relations between the ventilation performance metric defined in this paper and those defined previously are derived. The theoretical results of this paper are consistent with published experimental findings.

Contractor's marketing success.

              

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