control

Room pressure differential is an important aspect in order to guarantee sufficient contamination control, but is difficult to control in airtight cleanrooms. This research uses simulation models to get an understanding and to quantify the room pressure controllability of airtight cleanrooms. The most influential parameters on the room pressure controllability are identified using a sensitivity analysis. The effects of the shell airtightness and overflow flowrates are quantified, and the effect of a flow/pressure cascade with three coupled rooms is investigated.

Over the last decade, TVOC sensors have been touted as an interesting alternative to CO2 and RH sensors in DCV systems. Nevertheless, there is little evidence on the nature and the profile of TVOC concentrations in modern dwellings.

Since 2006, the French Energy Performance regulation, named RT, has been allowing two ways to justify building airtightness: either with a measurement or with the application of a quality management approach. The quality management approach certification is managed by the French Ministry in charge of construction, for which it set up a specific expert committee to assess quality management approaches. Since 2012, the justification has been compulsory for residential buildings. This obligation led to a more systematic use of certified quality management approaches.

Envelope airtightness is incorporated in the French Energy Performance (EP) Regulation (named “RT”) and is a key factor in the reduction of energy consumption. From 2006 until 2012, the French 2005 Energy Performance Regulation (RT, 2005) did not require justification of envelope airtightness. However, constructors could get certification for airtightness through a quality management (QM) approach, in order to build better-than-regulatory buildings.

The environmental conditions experienced in UK schools not only influence the effectiveness of teaching and learning but also affect energy consumption and occupant behaviour plays a critical role in determining such conditions.

While people need to know tomorrow’s weather to decide suitable activities and precautions, so do the “intelligent” building management systems. The accuracy of the short-term prediction of the ambient conditions is particularly import for the development  of predictive control strategies.

Natural ventilation is generally accepted as the preferred ventilation option as it is a healthy and energy-efficient means of supplying fresh air to a building. In the USA it is seldom being applied as most climate zones are considered unsuited to apply natural ventilation, mostly due to perceived uncontrollability and very humid and hot or very cold seasons. For mid and high rise apartment buildings the option of natural ventilation is virtually disregarded because the tradition of full air conditioning is so well established.

Cooling loads in office buildings with large glazing facades are increase due to solar radiation penetrating the windows and over-heating the rooms. Moreover solar radiation provides natural lighting in the rooms, which might be higher than expected in the summer months and causes glare problems. In order to balance optimally between the reduction of cooling loads and natural lighting a controller can be applied to select the best combination between the position of blinds and whether the artificial lights will operate or not. 

Since January 1st 2013, the French energy performance (EP) regulation requires building airtightness level to be justified to a lower-than-required value. These requirements represent an important change in the airtightness market. As a consequence, it is the State’s responsibility to accompany this market evolution and to supervise the implementation of the quality in building airtightness. French regulation allows two ways to justify the airtightness value for the building envelope.