mechanical ventilation

Indoor air pollution can pose a serious threat to human health and can increase the risk of early mortality. Studies have shown that human exposure to indoor pollution is more common than to outdoor pollution, especially where people spend the majority of their time indoors at home. Heating, ventilating, and air conditioning (HVAC) systems are used in buildings to regulate internal climate to improve the comfort level for occupants. In addition, ventilation rates are often increased to maintain appropriate Indoor Air Quality (IAQ).

Sleep is essential for overall health and well-being. The quality and efficiency of sleep are strongly influenced by the sleep environment, including indoor air quality. This study investigates the influence of mechanical ventilation on bedroom air quality during sleep and its impact on sleep efficiency and quality. Objective and subjective measurements were conducted to assess the effects of operating a mechanical ventilation system.

The future needs of indoor spaces in our buildings are likely to be cooling focused. With the widespread use of air-conditioning (AC) on the horizon there is now a need to ensure our systems perform as renewables (under the relevant definitions). A key part of tackling the uptake in energy intensive AC is likely to be the balancing of AC with renewable natural and mechanical ventilative cooling (VC).

The common demand control approach for MVHR systems using one CO2 sensor within the ventilation unit is assessed based on a typical residential apartment situation using CONTAM models. The simulation results confirm that air flow and therefore fan electricity and ventilation losses can be reduced compared to constant flow control, in particular for higher nominal air exchange rates. However, under certain boundary conditions, e.g. unevenly occupied dwellings indoor air quality in certain rooms may suffer with this DCV strategy.  

Duct routing often poses a great challenge when planning the installation of a mechanical ventilation system with heat recovery. This is particularly true for retrofits, where the necessary space for supply and exhaust ducts was originally not accounted for. This extended summary presents an alternative approach for duct routing avoiding ducts in the dwelling, while allowing the installation of a centralized MVHR unit and the implementation of a cascading airflow through the dwelling.

Mechanical ventilation has become a mandatory requirement in multiple European standards addressing indoor air quality (IAQ) and ventilation in residential dwellings (single family houses and low-rise apartment buildings). This article presents the state of the art study through a review of the existing literature, to establish a link between ventilation rate and key indoor air pollutants. Design characteristics of a mechanical ventilation system such as supply/exhaust air flow, system and design of supply and exhaust outlets were considered.

Noise from domestic ventilation systems is currently a little understood problem in the UK. Other European countries that have a longer history of using mechanical domestic ventilation systems have introduced noise limits for these systems. Without mandatory limits for noise in UK, noise is not a factor that is often considered during the design. However, noise can be a significant constraint to the use of ventilation systems. Research is reviewed from across Europe and North America that indicates residents turn off ventilation equipment with objectionable noise.

This study presents a comparison of three ventilation systems; automated Natural Ventilation (NV), balanced Mechanical Ventilation (MV) with heat recovery and Hybrid Ventilation (HV) with heat recovery for a new build office building.
The energy demand for heating and electricity as well as the indoor climate of the building were simulated using IESVE. Three key European cities were selected (Copenhagen, Munich and London) in order to investigate the applicability of the principles to different climatic conditions in Europe.

More than 64 million pupils spend more time in school than in any other place except home in Europe (European Commission, 2014). The indoor air quality is often a challenge in existing school buildings and the lack of proper ventilation often leads to negative effects like increased absenteeism and sick building syndrome symptoms as well as lowered performance amongst students compared to new buildings.

In 2008 the State of California adopted new building codes that required the use of mechanical ventilation systems in homes that meet the requirements of ASHRAE Standard 62.2. The standard requires both a dwelling unit mechanical ventilation system and exhaust fans in kitchens and bathrooms. A field study was undertaken to evaluate the IAQ and ventilation performance of homes built to these requirements. For ventilation system performance, the airflows of all mechanical ventilation systems were measured and their use was monitored for a one-week period.