English

The procedure of incorporating duct leakage into the T-method simulates leakage as an additional parallel section with zero length for each duct section. The assumption that additional air leakage creates additional system resistance is wrong. Leakage always reduces, not increases, system resistance. How fan power consumption changes due to leakage depends on the fan performance curve.  Methodology was developed to add duct leakage to the T-method previously developed for both the design and simulation of duct systems. It is shown that in most cases the sealing of ductwork is economical.

ASHRAE currently provides little practical information for optimizing the design of a cigar or smoking lounge, although recent ASHRAE forums have indicated an increased interest in this area. This paper provides a summary of the measurement of environmental tobacco smoke (ETS) from cigarettes or cigars, the manner in which ETS concentration varies with rates of smoking and ventilation, and the relationship between ETS concentration and indoor air quality.

This paper gives an account of a project to test the effectiveness of simple passive strategies to improve thermal comfort in Government Primary Schools in Pakistan .. Changes for improved thermal performance were carried out on five schools which were monitored both before and after modification. Schools are simple and minimally serviced. Improvements were controlled (as far as possible) to one strategy per classroom to make evaluation as straightforward as possible. An effectiveness score for a range of options has been developed.

Many methods of estimating energy savings from measured weather-dependent energy consumption data attempt to compensate for varying weather conditions between the pre- and post-retrofit periods by identifying an empirical model of pre-retrofit energy consumption and outdoor air temperature. Even though the pre-retrofit model may include a balance-point or change-point temperature, savings determined using this method implicitly assume that the indoor air set-point temperature and internal heat gains are the same during the pre- and post-retrofit periods.

Blower doors are used to measure the airtightness and air leakage of building envelopes. As existing dwellings in the United States are ventilated primarily through leaks in the building shell (i.e., infiltration) rather than by whole-house mechanical ventilation systems, quantification of airtightness data is critical in order to answer the following kinds of questions: What is the construction quality of the building envelope? Where are the air leakage pathways? How tight is the building? Tens of thousands of unique fan pressurization measurements have been made of U.S.

ASHRAE Research Project 806, Design Criteria for Building Ventilation Inlets, reviews existing knowledge of the placement of ventilation air louvers, produces a design guide, and suggests additional research, all with the intention of improving indoor air quality in commercial and institutional buildings. Decisions about intake and exhaust placements made early in the architectural and H VAC system design processes will impact occupants over the life of a building. Such placement decisions, therefore, require proper consideration.

The present Government has a target for reduction of the UK's carbon dioxide emissions of 20% of 1990 levels by the year 2010, which is in fact greater than the legal commitment set at the Kyoto summit on climate change in December 1997. Energy use in buildings accounts for approximately half of tl1e UK's annual carbon dioxide emissions and thus a reduction in the energy used in buildings is vital for this target to be achieved. A detailed knowledge of how energy is currently used is essential for assessing the potential for reducing the UK's C02 emissions.

The rising stream around a human body attributable to metabolic heat can carry contaminants from the floor level to the human breathing system. Thus, the quality of the breathing air greatly depends on the concentration distribution in the lower part of the room and the characteristics of the local air motion around the body. In this paper, a modeled human body (computational thermal manikin) is placed in a room that is air-conditioned with a displacement ventilation system.

This study established a research facility where airflow velocities, temperature, and differential pressures could be measured at the ridge of an attic. Following the construction of a test building, sensors were constructed, calibrated, and installed inside the attic. Paired tests were performed for three different ridge vent treatments; two were rolled type vents and one was a baffled vent.

Attic ventilation 1/150 and 1/300 rules of thumb were established to avoid problems from indoor moisture. In cold regions another strong reason to ventilate roofs that slope to cold eaves is to prevent the formation of problematic icicles and ice dams. Building heat, not the sun, is responsible for the large icings that cause such problems, and roof ventilation is a direct and effective way of solving them. The authors have instrumented buildings to determine attic ventilation needs to minimize icings and have developed design guidelines for natural and mechanical ventilation systems.