"I am very confident of the concreteness and airtightness of Judge Navarro's findings."
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Improving a building's airtightness and providing adequate ventilation—which would include recovering energy from exhaust air in order to condition fresh incoming air—can simultaneously reduce energy costs and dramatically improve indoor air quality.
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Furthermore,another report was produced in close collaboration with the AIVC, "Building airtightness: a critical review of testing reporting and quality schemes in 10 countries",F. R. Carrie, P. Wouters: "TN 67: Building airtightness: a critical review of testing, reporting and quality schemes in 10 countries", AIVC, 2012 in 2012; a review of testing and reporting about building airtightness and quality management issues for achieving a good airtightness in 10 countries.In 2013, TightVent Europe published "Building and ductwork airtightness: Selected papers from the REHVA special journal issue on ‘airtightness’" TightVent Europe: "Building and ductwork airtightness: Selected papers from the REHVA special journal issue on ‘airtightness’", 2013 composed of relevant contributions from the special issue on airtightness of the REHVA journal.
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W. Anis : "The changing requirements of airtightness in the US", proceedings of the AIVC -TightVent Workshop: "Building & Ductwork airtightness: Design, Implementation, Control and Durability: Feedback from Practice and Perspectives", 18–19 April 2013 There are several voluntary programs that require a minimum airtightness level for the building envelope (Passivhaus, Minergie-P, Effinergie etc.). Historically, the Passivhaus standard, originated in 1988 was the cornerstone for envelope airtightness developments because these types of buildings require extremely low leakage levels (n50 below 0.6 ach).
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Duct leakage test in the US A duct leakage tester is a diagnostic tool designed to measure the airtightness of forced air heating, ventilating and air-conditioning (HVAC) ductwork. A duct leakage tester consists of a calibrated fan for measuring an air flow rate and a pressure sensing device to measure the pressure created by the fan flow. The combination of pressure and fan flow measurements are used to determine the ductwork airtightness. The airtightness of ductwork is useful knowledge when trying to improve energy conservation.
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4 (11), 2011. CAN/CGSB-149.10-M86,CAN/CGSB Standard 149, “Determination of the Airtightness of Building Envelopes by Fan Depressurization Method”, Canadian General Standards Board, 1986 CAN/CGSB-149.15-96,CAN/CGSB Standard 149.15-96, “Determination of the Overall Envelope Airtightness of Buildings by the Fan Pressurization Method Using the Building's Air Handling Systems”, Canadian General Standards Board, 1996 ISO 9972:2006 (now superseded), & EN 13829 which is now 'withdrawn' due to the updated ISO 9972:2015.
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TightVent Europe publishes a biannual newsletter with up to date information on developments in respect to building and ductwork airtightness, including policy issues, publications, events, innovative technologies, case studies and research activities.
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This pressurization technique is described in standard test methods such as EN 12237 and EN 1507, ASHRAE standard 90.1-2010. It is similar in principle to that used to characterize building airtightness.
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Log houses have the same advantages as mentioned above. The material wood offers also a good heat insulation and a good airtightness can be reached by filling the gaps with moss and clay.
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Industry standards are often rules of thumb, developed over many years, that offset many conflicting goals: what people will pay for, manufacturing cost, local climate, traditional building practices, and varying standards of comfort. Both heat transfer and layer analysis may be performed in large industrial applications, but in household situations (appliances and building insulation), airtightness is the key in reducing heat transfer due to air leakage (forced or natural convection). Once airtightness is achieved, it has often been sufficient to choose the thickness of the insulating layer based on rules of thumb. Diminishing returns are achieved with each successive doubling of the insulating layer.
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CFM25 is defined as the air flow (in cubic feet per minute) needed to create a 25 Pascal pressure change in the ductwork. CFM25 is one of the most basic measurements of ductwork airtightness. A pressure of 25 Pa is equal to 0.1 inches (0.25 cm) of water column.
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The target audience of the TightVent Europe activities ranges from the research community over designers, practitioners, supply industry to European, national and regional government policy makers. It includes policy makers, training centres, designers, engineers and builders, air leakage testers, local and national airtightness associations, research and technical centres.
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However, attenuators, dampers, access panels, etc. are a part of the ductwork even if they have more functions than conveying the air and are therefore also referred to as technical ductwork products. Ductwork airtightness is the fundamental ductwork property that impacts the uncontrolled leakage of air through duct leaks.
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NFPA enclosure integrity testing is a specialized type of enclosure testing that typically measures the airtightness of rooms within buildings that are protected by clean agent fire suppression systems. This test is normally done during the installation and commissioning of the system and is mandatory under NFPA, ISO, EN and FIA Standards that also require the test is repeated annually if any doubt exists about the airtightness from the previous test. These types of enclosures are typically server rooms containing large amounts of computer and electronic hardware that would be damaged by the more typical water based sprinkler system. The word "clean" refers to the fact that after the suppression system discharges, there is nothing to be cleaned up.
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Leakage area estimates can also be normalized for the size of the enclosure being tested, For example, the LEED Green Building Rating System has set an airtightness standard for multifamily dwelling units of of leakage area per of enclosure area, to control tobacco smoke between units. This is equal to 0.868 cm²/m².
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The passivhaus standard combines superinsulation with other techniques and technologies to achieve ultra-low energy use. Superinsulation is an approach to building design, construction, and retrofitting that dramatically reduces heat loss (and gain) by using much higher levels of insulation and airtightness than normal. Superinsulation is one of the ancestors of the passive house approach.
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The thermal envelope defines the conditioned or living space in a house. The attic or basement may or may not be included in this area. Reducing airflow from inside to outside can help to reduce convective heat transfer significantly.BERC - Airtightness Ensuring low convective heat transfer also requires attention to building construction (weatherization) and the correct installation of insulative materials.
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Many if not most uses of ACH are actually referring to results of a standard blower door test in which 50 pascals of pressure are applied (ACH50), rather than the volume of air changed under normal conditions. The Passive House standard requires airtightness so that there will be less than 0.6 ACH with a pressure difference between inside and outside of 50 Pa.
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Blower door installation (France) Depending on how a blower door test is performed, a wide variety of airtightness and building airflow metrics can be derived from the gathered data. Some of the most common metrics and their variations are discussed below. The examples below use the SI pressure measurement unit Pascal (pa). Imperial measurement units are commonly water column inches (WC Inch or IWC).
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Building airtightness levels can be measured by using a fan, temporarily installed in the building envelope (a blower door) to pressurize the building. Air flow through the fan creates an internal, uniform, static pressure within the building. The aim of this type of measurement is to relate the pressure differential across the envelope to the air flow rate required to produce it. Generally, the higher the flow rate required to produce a given pressure difference, the less airtight the building. The fan pressurization technique is also described in many standard test methods, such as ASTM E779 - 10,ASTM, Standard E779-10, “Test Method for Determining Air Leakage by Fan Pressurization”, ASTM Book of Standards, American Society of Testing and Materials, Vol. 4 (11), 2010 ASTM E1827 – 11,ASTM, Standard E1827-11, “Standard Test Methods for Determining Airtightness of Buildings Using an Orifice Blower Door”, ASTM Book of Standards, American Society of Testing and Materials, Vol.
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Under some low energy building, passive house, low-energy house, self-sufficient homes, zero energy building, and superinsulation standards, structures must be more air-tight than other lesser standards. Air barriers are not effective if construction joints or service penetrations (holes for pipes, etc.) are not sealed. Airtightness is a measure of the amount of warm (or cool) air that can pass through a structure. Mechanical ventilation system can recover heat before discharging air externally.
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645Z medium format camera In March 2010 Pentax announced its first medium format digital camera, the Pentax 645D. The camera has been in and out of development since 2003 and went on sale in Japan in May 2010 at RRP of ¥850,000, with supplies to the rest of the world expected to start soon after. It is targeted at professionals doing outdoor photography—camera body features very high level of airtightness. It uses a 40 megapixels, 44 mm × 33 mm CCD sensor.
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A capsule for transporting packages using the Prague pneumatic post network The system uses aluminium capsules measuring 48 mm in outer-diameter and 200 mm in length. On the rear end they are fitted with a plastic circlet, preventing friction against walls of the pipe and a soft plastic skirt, sealing air behind the capsule. The diameter of the rear circlet is 57 mm. The remaining 8 millimeters of the bore are sealed just by the skirt, allowing for excellent airtightness and low friction at the same time.
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Airtightness and life support systems were in order until the moment of > catastrophic fall, as indicated by barometric recorder and Vasenko's log > entries ending at 16:13. > 6\. During the last 9.5 minutes of the fall the crew tumbled inside the > rotating gondola, but all crew members remained vertical until the end; > their deaths were caused by the final impact. > Conclusion: The flight was substantially safe up to 19,500 meters; 20,500 > meters was on the edge but presented no imminent danger; ascent to 22,000 > meters led to an inevitable accident.
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Concrete stave silo under construction in 2015 Storage silos are cylindrical structures, typically 10 to 90 ft (3 to 27 m) in diameter and 30 to 275 ft (10 to 90 m) in height with the slipform and Jumpform concrete silos being the larger diameter and taller silos. They can be made of many materials. Wood staves, concrete staves, cast concrete, and steel panels have all been used, and have varying cost, durability, and airtightness tradeoffs. Silos storing grain, cement and woodchips are typically unloaded with air slides or augers.
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Simplified schematic diagram of blower door pressure testing Blower door technology was first used to measure building airtightness in Sweden around 1977. This earliest implementation used a fan mounted in a window, rather than a door. Similar window-mounted measurement techniques were being pursued by Caffey in Texas, and door-mounted test fans were being developed by Harrje, Blomsterberg and Persily at Princeton University to help them find and fix air leaks in homes in a Twin Rivers, New Jersey housing development. Harold Orr has also been identified as a member of a group in Saskatchewan, Canada who was pursuing similar testing methods.
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In Wales where 'zero-carbon homes' are the aspiration for 2011 (although 2012 is more likely) the requirements are for Code for Sustainable Homes or equivalent. This has opened the doors for standards like Passiv Haus and the CarbonLite programme. Another lesser known building type that does not rely on airtightness in order to get its energy rating is Bio-Solar-Haus. This is not a well known type of house, but it has a range of positive advantages like it is built out of renewable resources and it is a breathable structure thus making it much healthier to live in.
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Ductwork airtightness can be defined as the resistance to inward or outward air leakage through the ductwork envelope (or ductwork shell). This air leakage is driven by differential pressures across the ductwork envelope due to the combined effects of stack and fan operation (in case of a mechanical ventilation system). For a given HVAC system, the term ductwork refers to the set of ducts and fittings (tees, reducers, bends, etc.) that are used to supply the air to or extract the air from the conditioned spaces. It does not include components such as air handlers, heat recovery units, air terminal devices, coils.
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This is calculated using the Government's Standard Assessment Procedure for Energy Rating of Dwellings (SAP 2005).Standard Assessment Procedure for Energy Rating of Dwellings 2005, Building Research Establishment In addition to the levels of insulation provide by the structure of the building, the DER also takes into account the airtightness of the building, the efficiency of space and water heating, the efficiency of lighting, and any savings from solar power or other energy generation technologies employed, and other factors. For the first time, it also became compulsory to upgrade the energy efficiency in existing houses when extensions or certain other works are carried out.
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The Centre holds annual conferences and workshops,Building Ecology, "AIVC - Air Infiltration and Ventilation Centre", Retrieved May 2014 publishes papers and reports, and maintains a large database of publications. The AIVC also collaborates with the TightVent Europe and venticool platforms; both platforms are market oriented, created in 2011 and 2012 and focusing on building and ductwork airtightness and ventilative cooling strategies in buildings, respectively. In addition, the AIVC has collaborative activities with organizations such as the International Society of Indoor Air Quality and Climate, the Federation of European Heating, Ventilation and Air-conditioning Associations, the International Building Performance Simulation Association, the American Society of Heating, Refrigerating and Air Conditioning Engineers as well as the Indoor Environmental Quality Global Alliance.
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The Institute believes that this approach to the Standard is essential, as North America has variety of different climates and different passive measures may be more effective than others. The standard is based on five principles: airtightness, ventilation, waterproofing, heating and cooling, and electrical loads. Within these principles, projects must pass building specified blower door, ventilation airflow, overall airflow, and electrical load tests; buildings must also achieve other measures such as low- emission materials, renewable energy systems, moisture control, outdoor ventilation, and energy efficient ventilation and space conditioning equipment. All buildings must also pass a quality assurance and quality control test – this is implemented to ensure that the building continues to adhere to the regional criteria set forth by the PHIUS’ climate data.
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