English

Cooking can be a major source of exposure to particulate matter. Range hoods can be used to reduce odours, moisture and contaminants resulting from cooking. The capture efficiency with regard to these contaminants is determined by the thermal plume and the aerodynamic properties of the range hood. There is a new ASTM (an international standards organization) test method: ASTM E3087. It measures capture efficiency under specific conditions that permits standardized comparison of range hoods under controlled laboratory conditions.

Cooking is one of the most substantial sources of indoor air pollution in most residences.  This is mitigated most often by exhaust devices located near cooking surfaces.  In this study, we measured the efficacy of one type of kitchen ventilation device: an island overhead kitchen exhaust.  Laboratory tests using tracer gas capture were performed on a full-scale mock-up of a kitchen with a cooktop in an island. The results show that the Capture Efficiency (CE) varies greatly from about 10% to nearly 100%.

Exposures to elevated concentrations of fine particulate matter with diameter ≤2.5µm (PM2.5) are linked to multiple acute and chronic health effects, including increased risk of cardiovascular and respiratory disease. As people spend up to 70% in their own homes, exposures to pollutants indoors could have a greater impact on health than exposure outdoors. Cooking is a primary emission source of PM2.5 in dwellings, and is of interest as it is an activity conducted several times a day in most households.

The research question of this report is “Is it possible to save energy by lowering the bedroom temperatures in winter”. In this paper first the literature on optimum sleeping temperatures is investigated. Then bedroom temperatures and CO2 levels in a cold week in March 2018 are investigated in 16 bedrooms of students of the Master course Technoledge Climate Desing in 2017-2018 of the faculty of Architecture and the Built Environment of the Delft University of Technology. This study shows that it must be possible to save energy by lowering the bedroom temperature in winter.

There has been an increase in diseases caused by airborne infections such as influenza A/H1N1 or SARS in the recent years. Airborne infection isolation rooms are commonly used to limit the spread of airborne infections. The challenge today is that there is only a limited number of airborne infection isolation rooms in each hospital (class P4). The rooms are expensive to build and airflow control to avoid contamination is often complicated.

Ventilation and healthy classes are a recurring problem. Continuously increasing the air flow rate improves the living environment, but is unacceptable in terms of higher costs and energy loss, which is why a different approach is needed. The research question asked in this study is : Is a central ventilation system operating at low power, but combined with a decentralised ventilation system with heat recovery, more economical and energy efficient and at the same time does it provide the premises with a constant and good air quality?

This paper presents results from a project on the assessment of the indoor air quality (IAQ) benefits that might accrue from the use of a balanced energy recovery ventilation system. The study compared the whole-building pressure, IAQ and ventilation performance of a balanced energy recovery ventilation (ERV) system with that of an exhaust-only ventilation system (continuous exhaust from master bathroom).

This article proposes to study the impact of envelope and internal partition walls airleakage distributions, on the indoor air quality (IAQ) performance. It is based on a preliminary performance-based approach using formaldehyde with three emission levels (low, medium, high). This multizone modelling (CONTAM) approach uses as performance indicators, the average concentration per room as well as the percentage of time of exceeding the limit value (ELV) of 9 µg.m-3.

The implementation of decentralised ventilation units is growing, especially in the residential retrofit. These systems are typically simple to install on site (usually in the external façade with no additional ductwork) and allow room-by-room control strategies. Until now, decentralised systems are evaluated by applying the same methodologies as for centralised ventilation systems, even though different boundary conditions apply. Some differences are for example:  

Diffuse ceiling ventilation is a novel air distribution concept, where the space above a suspended ceiling is used as a plenum and fresh air is supplied into the occupied zone through perforations in the suspended ceiling panels. Due to the low momentum supply, the airflow in the room is driven by buoyancy force generated by heat sources. The previous studies indicate that the diffuse ceiling ventilation system can effectively eliminate the draught risk in the occupied zone and provide a comfortable indoor environment even with low-temperature supply.