English

In equatorial warm humid climates, ventilation has been largely adopted as a major strategy for natural passive cooling. In those climates the use porous elements are common to allow for permanent ventilation as temperature rarely drops below 20°C. Nevertheless, the performance of many building components has not been thoroughly determined, making it difficult to predict buildings performance as ventilation rates, estimated in most simulation codes are often based on apertures typologies from temperate and cold regions.

This Update discusses how various factors affect the fire resistance of floors in multi-family dwellings. The information is based on results from a major industry/government research project carried out by the National Research Council's Institute for Research in Construction (IRC). 

 False fire alarms cost lives and students are often the worst offenders because of their less than silky cooking skills. HAC reveals how an 'allergy' to washing up liquid led to an innovative demand ventilation solution at Nottingham Trent University.          

This article presents the study of a surgical block with serious deficiencies of Indoor Air Quality (IAQ) located in the Hospital del Rio Hortega (Valladolid, Spain). Block characteristics were identified and symptoms reports collected from 118 workers. At the end of the initial investigation, it was concluded that there was Sick Building Syndrome. Measurements of ventilation and contaminants were made of indoor air (CO, C02, TVOC, anaesthetic gases, at six different points simultaneously) and outdoor air (hospital incinerator).

This guide is divided into four sections, which draw together different areas of BRE radon-related research. It supplements existing guidance. Sump systems are usually very effective at reducing indoor radon levels. The first part of the guide describes the benefits of passive sump systems, ie systems that are not fan-assisted. The second part shows how a single fan-assisted system can be used to treat several adjoining houses. Compared to installing several separate systems, a communal system of this type is quicker and cheaper to install and causes less disruption.

A mathematical model is developed to predict Volatile Organic Compound (VOC) emission rates from homogeneous materials. The model considers both mass diffusion and mass convection processes in the boundary layer between the material surface and the air flow. Establishing the relationship between the surface air flow and emission rate: the model therefore can predict the material emission rate under different environmental conditions.

The present paper aims to investigate, in a systematic way, and by using both experimental and theoretical tools, the potential of night ventilation techniques when applied to full scale buildings, under different structure, design, ventilation, and climatic characteristics. Also, to investigate the impact and the limitations of night ventilation techniques regarding the thermal behavior of various types of buildings. Real scale measurements in three buildings operating under free-floating and air conditioning conditions have been performed.