English

Residential ventilation systems can be categorized as supply, exhaust, or balanced systems.This effort focused on establishing a design methodology for central-fan-integrated supplyventilation systems. Air flow measurements were taken for 7.6 m lengths of 12.7 cm through22.9 cm diameter flexible ducts, with a 15.2 cm wall-cap, at duct pressures of -10 Pa to -120Pa. Using these measurements and field experience, a five-step method was developed as aguide for sizing and installing the ventilation system.

In order to estimate air change rates (ACH) on Natural Ventilation (NV) processes a number of factors should be known as general and openings dimensions, pressure distribution over the facades, internal heat sources (or sinks) and head losses. The atmospheric boundary layer (ABL) characteristics change with the terrain roughness and affect the pressure distribution. Construction features determine infiltration rates, flow regimes through openings and its head losses so affecting the internal airflow.

Isolation rooms for Tuberculosis in fifteen hospitals have been surveyed and measured in twophases. In phase 1 the isolation rooms in seven hospitals were checked ater the hospitalsrenovation construction had been finished. However in phase 2 all the design drawings of theair-conditioning and ventilation/exhaust system of isolation rooms in eight other hospitalswere checked and revised by ERLs engineer before starting construction. The survey itemsinclude ventilation rate ' static pressure ' temperature and humidity.

The present study introduces a humidity control apparatus which can hygienically and automaticlymaintain the appropriate humidity level of indoor air without either a water supply or drainage system.In humidification, the desiccant takes up water vapor from the outdoor air in the adsorption process,and releases it indoors by desorption. Therefore, no water supply is required to humidify. An apparatus havingno water supply is more hygienic, because it does not propagate bacteria and does notscatter the calcium and magnesium salts found in the water.