In the realm of home comfort, few appliances are as crucial as the air conditioning system, particularly during sweltering summer months. A significant component of this system is the thermostat, which serves as the command center for temperature regulation. However, just like any electronic device, thermostats can encounter malfunctions that necessitate emergency AC repair. Specifically, issues related to thermostat malfunctions often demand immediate attention due to their potential impact on overall system performance and energy efficiency.
HVAC Repair specialists can fix issues with your air conditioner, furnace, or ductwork HVAC maintenance to optimize your heat exchanger performance.
One common issue that requires urgent intervention is incorrect temperature readings. When a thermostat inaccurately measures room temperature, it may lead to overcooling or undercooling your living space. This miscalculation not only causes discomfort but can also strain your AC unit by forcing it to work harder than necessary, potentially leading to premature wear and increased energy bills.
Another prevalent problem is connectivity issues in smart thermostats. These devices rely on a stable internet connection to function optimally and provide features such as remote access and energy usage reports. Connectivity problems can disrupt these functions and hinder the ability to control your home's climate efficiently.
Additionally, a malfunctioning thermostat might suffer from unresponsive controls or display glitches. In such cases, users may find themselves unable to adjust settings or receive accurate feedback about their home's environment, making it essential to address these concerns promptly.
To mitigate these issues and avoid costly repairs or replacements, recalibrating a smart thermostat can be an effective solution. Recalibration ensures that the thermostat accurately senses temperature changes and communicates effectively with your HVAC system. To recalibrate a smart thermostat:
1. **Consult the Manual**: Start by reviewing the manufacturer's instructions for recalibrating your specific model since procedures may vary between brands.
2. **Check Placement**: Ensure that the thermostat is placed away from direct sunlight, drafts, or heat sources that could skew its readings.
3. **Perform a Reset**: Most smart thermostats have an option for resetting them either through software settings or physical buttons on the device itself.
4. **Update Software**: Regularly update your thermostat's firmware if applicable; manufacturers may release patches that fix bugs affecting performance.
5. **Test Accuracy**: After recalibration, use an independent thermometer to verify whether your thermostat now provides accurate readings.
By addressing these common issues through timely recalibration of smart thermostats, homeowners can maintain efficient operation of their AC systems while enhancing comfort levels within their living spaces all year round.
In today's technologically advanced world, smart thermostats have become an integral part of many households, offering significant energy savings and enhanced convenience. These devices are designed to learn from user behaviors and environmental changes to optimize heating and cooling settings. However, like any sophisticated system, they require occasional recalibration to maintain peak performance. Understanding when and why recalibration is necessary can ensure that your smart thermostat continues to function effectively.
Recalibration refers to the process of adjusting the internal settings of a device to ensure accuracy in its operations. For smart thermostats, this usually involves checking temperature sensors, updating firmware, or resetting system algorithms. The need for recalibration can arise due to various factors such as seasonal changes, shifts in household routines, or even software updates that might alter how the thermostat interprets data.
One crucial reason for recalibrating a smart thermostat is the change of seasons. As temperatures fluctuate between summer and winter extremes, what was once an ideal setting may no longer be efficient or comfortable. During these transitions, recalibrating ensures that your device accurately senses ambient temperatures and adjusts heating or cooling systems appropriately. This not only maintains comfort but also optimizes energy use by preventing unnecessary heating or cooling cycles.
Another factor necessitating recalibration is lifestyle changes within a household. If there's a new baby in the house requiring warmer temperatures at night or if family members start spending more time at home during certain hours because of remote working arrangements, it's essential for the thermostat to adapt accordingly. Regularly updating its settings helps align with these lifestyle shifts and enhances overall efficiency.
Furthermore, software updates can sometimes reset default settings on smart thermostats or introduce new features that require fine-tuning for optimal performance. After such updates are installed-whether manually initiated by users or automatically pushed by manufacturers-it's wise to check if everything functions as expected and make adjustments where needed.
To effectively recalibrate your smart thermostat, begin by consulting the user manual specific to your model as procedures can vary widely across different brands and units. Generally speaking though: start with assessing current schedules set on your device ensuring they match actual usage patterns then verify temperature readings against another reliable thermometer placed nearby; slight discrepancies might indicate sensor misalignment needing correction via calibration mode offered through most units' interfaces today.
In conclusion: while modern technology gifts us incredible conveniences like those provided via intelligent climate control systems found embedded within contemporary homes everywhere now-they still demand upkeep too!
Recalibrating a smart thermostat is an essential task that ensures your device operates efficiently and maintains the desired comfort levels in your home. Before diving into the recalibration process, however, it is crucial to safely turn off the power to avoid any electrical mishaps or damage to the unit. This step-by-step guide will walk you through the process of safely powering down your system before recalibration.
First and foremost, understanding why turning off the power is necessary can reinforce its importance. Electrical devices like smart thermostats are sensitive, and working on them while they are powered can lead to short circuits or other forms of damage. Moreover, turning off the power reduces any risk of electric shock during handling.
To begin with, identify where your home's main circuit breaker panel is located. Typically found in basements, garages, or utility rooms, this panel contains switches that control electricity flow throughout different sections of your house. Once located, open the panel door and look for a label indicating which switch controls the power to your HVAC system-this could be labeled as "HVAC," "Furnace," "Heating System," or something similar.
If you're unsure about which breaker connects to your thermostat specifically, it might be helpful to consult any documentation related to your home's electrical setup or even directly inspect where wiring from your HVAC system leads within the breaker box.
Recalibrating a smart thermostat is an essential task to ensure that your home's climate control system operates efficiently and accurately. Over time, even the most sophisticated thermostats can drift slightly from their original settings due to various factors such as power outages, firmware updates, or simply because of prolonged use. To maintain optimal performance, it is crucial to recalibrate your device periodically. This essay will provide detailed instructions on accessing the thermostat settings for recalibration, ensuring you can perform this task with confidence and precision.
First and foremost, it is important to identify the specific model of your smart thermostat since different models may have varying interfaces and menu options. Referencing the user manual provided by the manufacturer can be immensely helpful in locating the exact steps needed for recalibration. If you don't have a physical copy of the manual, most manufacturers offer digital versions on their websites.
Once you are familiar with your thermostat model's interface, begin by accessing its main menu. Typically, this can be done by tapping or pressing a button labeled "Menu" or navigating through touchscreen options if your device supports touch inputs. From here, look for settings related to calibration or temperature adjustment; these might be found under sections such as "Settings," "System," or "Advanced Settings." Again, consulting the user manual will guide you in finding these specific sections.
After locating the right section within your thermostat's menu system, select the option for recalibration or temperature offset. This function allows users to adjust what the thermostat perceives as current room temperature so that it aligns more closely with actual conditions. It's advisable to have an accurate thermometer on hand during this process so that you can compare readings between it and your smart thermostat.
Carefully follow any prompts given by your device during this stage-some thermostats might require confirmation before applying changes while others could automatically save adjustments once entered. When making temperature corrections, proceed incrementally. Small adjustments are recommended-often in increments of one degree Fahrenheit-to avoid drastic swings in heating or cooling operations that could disrupt comfort levels within your home.
Finally, after completing recalibration efforts via direct input into system menus on-screen (or through corresponding apps where applicable), monitor how well newly adjusted settings hold up over subsequent usage periods across varied environmental conditions inside living spaces served by said equipment types involved throughout procedures described herein today!
In conclusion: Recalibrating a smart thermostat involves understanding both technical aspects unique each individual product line plus practical considerations surrounding daily household routines impacted accordingly thereafter following completion thereof successfully undertaken steps outlined above comprehensively now shared among readers alike seeking enhance overall experience managing indoor climates effectively moving forward together harmoniously onward evermore!
Recalibrating a smart thermostat is an essential task to ensure that your home maintains the desired comfort levels while also optimizing energy efficiency. However, recalibration alone does not guarantee ongoing precision in temperature readings. It is crucial to follow certain tips and practices post-recalibration to ensure that your thermostat provides accurate readings consistently.
Firstly, after recalibrating your thermostat, it is important to verify its accuracy by cross-checking with a reliable thermometer. Place an independent thermometer near the thermostat and give both devices time to stabilize before comparing their readings. This step helps confirm whether the calibration was successful and if further adjustments are necessary.
Another critical factor is the placement of your smart thermostat. To maintain accurate temperature readings, it should be installed away from direct sunlight, drafts, windows, doors, or any heat-producing appliances. These elements can skew the temperature sensor's perception of the room's actual conditions, leading to inaccurate readings and suboptimal performance.
Regular maintenance plays a vital role in ensuring accurate temperature readings as well. Dust and debris can accumulate on or around the thermostat's sensors over time. Cleaning these areas gently with a soft cloth can prevent interference with its ability to measure temperatures accurately. Additionally, check for firmware updates regularly as manufacturers often release improvements that enhance sensor accuracy and overall functionality.
Furthermore, consider adjusting settings related to sensitivity if available on your device. Some advanced smart thermostats allow users to fine-tune how sensitive they are to changes in temperature or humidity levels. Adjusting these settings according to personal preferences and environmental factors can significantly improve reading accuracy.
It is also wise to monitor for any irregularities or fluctuations in temperature over time. Sudden spikes or drops might indicate underlying issues such as faulty wiring or problems with HVAC system components rather than miscalibration of the thermostat itself.
Finally, educate other household members about proper usage habits regarding heating/cooling systems controlled by smart thermostats - things like avoiding frequent manual overrides which could disrupt calibrated settings inadvertently affecting long-term accuracy.
By following these practical tips-verifying initial post-calibration results against external thermometers; ensuring optimal placement free from environmental interferences; committing regular cleaning/maintenance routines; staying updated with technological advancements through firmware updates; adjusting sensitivity settings where applicable; monitoring potential anomalies-and promoting informed usage among all users-you'll help ensure consistent reliability from your newly recalibrated smart thermostat thereby enhancing both comfort levels within living spaces along efficient energy management strategies employed throughout homes today!
Recalibrating a smart thermostat can be a straightforward task, but like any technical process, additional problems may occasionally arise. Troubleshooting these issues is essential to ensure that your smart thermostat functions optimally and maintains the desired comfort levels in your home.
One common problem that might occur during recalibration is connectivity issues. Smart thermostats rely on Wi-Fi for various functionalities such as remote access and updates. If you encounter connectivity problems, it's important to check your internet connection first. Ensure that the router is working properly and the thermostat is within range of the Wi-Fi signal. Restarting both the router and the thermostat often resolves minor glitches.
Another issue that could surface involves incorrect temperature readings. This can lead to inefficient heating or cooling cycles, which not only disrupts comfort but also increases energy bills. If you notice discrepancies in temperature readings, start by verifying the placement of your thermostat. It should be away from direct sunlight, drafts, and other heat sources like ovens or electronic equipment. Such placements can affect its sensor accuracy.
Power-related problems are also not uncommon when recalibrating a smart thermostat. Sometimes, after an update or a reset, the device may fail to power up correctly due to insufficient power supply from older HVAC systems that do not provide adequate voltage through C-wires (common wires). Installing a C-wire adapter or upgrading your system might be necessary if this problem persists.
Software bugs are another potential complication during recalibration processes. Manufacturers frequently release firmware updates to address known issues and improve functionality; however, these updates sometimes introduce new bugs instead.
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This article may rely excessively on sources too closely associated with the subject, potentially preventing the article from being verifiable and neutral. (June 2022)
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| Agency overview | |
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| Formed | October 1, 1977 |
| Jurisdiction | Federal Government of the United States |
| Headquarters | Washington, D.C. United States |
| Annual budget | $126.8 million (FY2021)[1] |
| Agency executives |
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| Parent agency | United States Department of Energy |
| Website | EIA.gov |
The U.S. Energy Information Administration (EIA) is a principal agency of the U.S. Federal Statistical System responsible for collecting, analyzing, and disseminating energy information to promote sound policymaking, efficient markets, and public understanding of energy and its interaction with the economy and the environment. EIA programs cover data on coal, petroleum, natural gas, electric, renewable and nuclear energy. EIA is part of the U.S. Department of Energy.
The Department of Energy Organization Act of 1977 established EIA as the primary federal government authority on energy statistics and analysis, building upon systems and organizations first established in 1974 following the oil market disruption of 1973.
EIA conducts a comprehensive data collection program that covers the full spectrum of energy sources, end uses, and energy flows; generates short- and long-term domestic and international energy projections; and performs informative energy analyses.
EIA disseminates its data products, analyses, reports, and services to customers and stakeholders primarily through its website and the customer contact center.
Located in Washington, D.C., EIA has about 325 federal employees and a budget of $126.8 million in fiscal year 2021.[1][2]
| Portrait | Administrator | Took office | Left office |
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Lincoln Moses | 1978 | 1980 |
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Erich Evered | 1981 | 1984 |
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Helmut Merklein | 1985 | 1990 |
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Calvin Kent | 1990 | 1993 |
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Jay Hakes | 1993 | 2000 |
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Guy Caruso | 2002 | 2008 |
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Richard G. Newell | August 3, 2009 | July 1, 2011 |
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Adam Sieminski | 2012 | 2017 |
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Linda Capuano | 2018 | 2021 |
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Joseph DeCarolis | April 11, 2022 | January 20, 2025 |
By law, EIA's products are prepared independently of policy considerations. EIA neither formulates nor advocates any policy conclusions. The Department of Energy Organization Act allows EIA's processes and products to be independent from review by Executive Branch officials; specifically, Section 205(d) says:
"The Administrator shall not be required to obtain the approval of any other officer or employee of the Department in connection with the collection or analysis of any information; nor shall the Administrator be required, prior to publication, to obtain the approval of any other officer or employee of the United States with respect to the substance of any statistical or forecasting technical reports which he has prepared in accordance with law."[3]
More than two million people use the EIA's information online each month. Some of the EIA's products include:
The Federal Energy Administration Act of 1974 created the Federal Energy Administration (FEA), the first U.S. agency with the primary focus on energy and mandated it to collect, assemble, evaluate, and analyze energy information. It also provided the FEA with data collection enforcement authority for gathering data from energy producing and major consuming firms. Section 52 of the FEA Act mandated establishment of the National Energy Information System to "… contain such energy information as is necessary to carry out the Administration's statistical and forecasting activities …"
The Department of Energy Organization Act of 1977, Public Law 95-91, created the Department of Energy. Section 205 of this law established the Energy Information Administration (EIA) as the primary federal government authority on energy statistics and analysis to carry out a " ...central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information which is relevant to energy resource reserves, energy production, demand, and technology, and related economic and statistical information, or which is relevant to the adequacy of energy resources to meet demands in the near and longer term future for the Nation's economic and social needs."[3]
The same law established that EIA's processes and products are independent from review by Executive Branch officials.
The majority of EIA energy data surveys are based on the general mandates set forth above. However, there are some surveys specifically mandated by law, including:
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Office of Cybersecurity, Energy Security, & Energy Response
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| Under Secretary of Energy for Science and Innovation | ||
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| Power Marketing Administration | ||
| National Laboratory System | ||
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This article needs additional citations for verification. (May 2009)
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A particulate air filter is a device composed of fibrous, or porous materials which removes particulates such as smoke, dust, pollen, mold, viruses and bacteria from the air. Filters containing an adsorbent or catalyst such as charcoal (carbon) may also remove odors and gaseous pollutants such as volatile organic compounds or ozone.[1] Air filters are used in applications where air quality is important, notably in building ventilation systems and in engines.
Some buildings, as well as aircraft and other human-made environments (e.g., satellites, and Space Shuttles) use foam, pleated paper, or spun fiberglass filter elements. Another method, air ionizers, use fibers or elements with a static electric charge, which attract dust particles. The air intakes of internal combustion engines and air compressors tend to use either paper, foam, or cotton filters. Oil bath filters have fallen out of favour aside from niche uses. The technology of air intake filters of gas turbines has improved significantly in recent years, due to improvements in the aerodynamics and fluid dynamics of the air-compressor part of the gas turbines.
Do-it-yourself air cleaner are low-cost alternative to commercial portable air cleaners.[2]
High efficiency particulate arrester (HEPA),[3][4] originally called high-efficiency particulate absorber but also sometimes called high-efficiency particulate arresting or high-efficiency particulate arrestance, is a type of air filter. Filters meeting the HEPA standard have many applications, including use in clean rooms for IC fabrication, medical facilities, automobiles, aircraft and homes. The filter must satisfy certain standards of efficiency such as those set by the United States Department of Energy (DOE).
Varying standards define what qualifies as a HEPA filter. The two most common standards require that an air filter must remove (from the air that passes through) 99.95% (European Standard)[5] or 99.97% (ASME standard)[6] of particles that have a size greater than or equal to 0.3 μm.
The cabin air filter, also known in the United Kingdom as a pollen filter, is typically a pleated-paper filter that is placed in the outside-air intake for the vehicle's passenger compartment. Some of these filters are rectangular and similar in shape to the engine air filter. Others are uniquely shaped to fit the available space of particular vehicles' outside-air intakes.
The first automaker to include a disposable filter to keep the ventilation system clean was the Nash Motors "Weather Eye", introduced in 1940.[7]
A reusable heater core filter was available as an optional accessory on Studebaker models beginning in 1959, including Studebaker Lark automobiles (1959-1966), Studebaker Gran Turismo Hawk automobiles (1962-1964) and Studebaker Champ trucks (1960-1964). The filter was an aluminum frame containing an aluminum mesh and was located directly above the heater core. The filter was removed and installed from the engine compartment through a slot in the firewall. A long, thin rubber seal plugged the slot when the filter was installed. The filter could be vacuumed and washed prior to installation.
Clogged or dirty cabin air filters can significantly reduce airflow from the cabin vents, as well as introduce allergens into the cabin air stream. Since the cabin air temperature depends upon the flow rate of the air passing through the heater core, the evaporator, or both, clogged filters can greatly reduce the effectiveness and performance of the vehicle's air conditioning and heating systems.[8]
Some cabin air filters perform poorly, and some cabin air filter manufacturers do not print a minimum efficiency reporting value (MERV) filter rating on their cabin air filters.[citation needed]
The combustion air filter prevents abrasive particulate matter from entering the engine's cylinders, where it would cause mechanical wear and oil contamination.
Most fuel injected vehicles use a pleated paper filter element in the form of a flat panel. This filter is usually placed inside a plastic box connected to the throttle body with duct work. Older vehicles that use carburetors or throttle body fuel injection typically use a cylindrical air filter, usually between 100 millimetres (4 in) and 400 millimetres (16 in) in diameter. This is positioned above or beside the carburetor or throttle body, usually in a metal or plastic container which may incorporate ducting to provide cool and/or warm inlet air, and secured with a metal or plastic lid. The overall unit (filter and housing together) is called the air cleaner.
Pleated paper filter elements are the nearly exclusive choice for automobile engine air cleaners, because they are efficient, easy to service, and cost-effective. The "paper" term is somewhat misleading, as the filter media are considerably different from papers used for writing or packaging, etc. There is a persistent belief among tuners, fomented by advertising for aftermarket non-paper replacement filters, that paper filters flow poorly and thus restrict engine performance. In fact, as long as a pleated-paper filter is sized appropriately for the airflow volumes encountered in a particular application, such filters present only trivial restriction to flow until the filter has become significantly clogged with dirt. Construction equipment engines also use this. The reason is that the paper is bent in zig-zag shape, and the total area of the paper is very large, in the range of 50 times of the air opening.[citation needed]
Oil-wetted polyurethane foam elements are used in some aftermarket replacement automobile air filters. Foam was in the past widely used in air cleaners on small engines on lawnmowers and other power equipment, but automotive-type paper filter elements have largely supplanted oil-wetted foam in these applications. Foam filters are still commonly used on air compressors for air tools up to 5 horsepower (3.7 kW). Depending on the grade and thickness of foam employed, an oil-wetted foam filter element can offer minimal airflow restriction or very high dirt capacity, the latter property making foam filters a popular choice in off-road rallying and other motorsport applications where high levels of dust will be encountered. Due to the way dust is captured on foam filters, large amounts may be trapped without measurable change in airflow restriction.[citation needed]
Oiled cotton gauze is employed in a growing number of aftermarket automotive air filters marketed as high-performance items. In the past, cotton gauze saw limited use in original-equipment automotive air filters. However, since the introduction of the Abarth SS versions, the Fiat subsidiary supplies cotton gauze air filters as OE filters.
Stainless steel mesh is another example of medium which allow more air to pass through. Stainless steel mesh comes with different mesh counts, offering different filtration standards. In an extreme modified engine lacking in space for a cone based air filter, some will opt to install a simple stainless steel mesh over the turbo to ensure no particles enter the engine via the turbo.
An oil bath air cleaner consists of a sump containing a pool of oil, and an insert which is filled with fiber, mesh, foam, or another coarse filter media. The cleaner removes particles by adhering them to the oil-soaked filter media rather than traditional filtration, the openings in the filter media are much larger than the particles that are to be filtered. When the cleaner is assembled, the media-containing body of the insert sits a short distance above the surface of the oil pool. The rim of the insert overlaps the rim of the sump. This arrangement forms a labyrinthine path through which the air must travel in a series of U-turns: up through the gap between the rims of the insert and the sump, down through the gap between the outer wall of the insert and the inner wall of the sump, and up through the filter media in the body of the insert. This U-turn takes the air at high velocity across the surface of the oil pool. Larger and heavier dust and dirt particles in the air cannot make the turn due to their inertia, so they fall into the oil and settle to the bottom of the base bowl. Lighter and smaller particles stick to the filtration media in the insert, which is wetted by oil droplets aspirated there into by normal airflow. The constant aspiration of oil onto the filter media slowly carries most of the finer trapped particles downward and the oil drips back into the reservoir where the particles accumulate.
Oil bath air cleaners were very widely used in automotive and small engine applications until the widespread industry adoption of the paper filter in the early 1960s. Such cleaners are still used in off-road equipment where very high levels of dust are encountered, for oil bath air cleaners can sequester a great deal of dirt relative to their overall size without loss of filtration efficiency or airflow. However, the liquid oil makes cleaning and servicing such air cleaners messy and inconvenient, they must be relatively large to avoid excessive restriction at high airflow rates, and they tend to increase exhaust emissions of unburned hydrocarbons due to oil aspiration when used on spark-ignition engines.[citation needed]
In the early 20th century (about 1900 to 1930), water bath air cleaners were used in some applications (cars, trucks, tractors, and portable and stationary engines). They worked on roughly the same principles as oil bath air cleaners. For example, the original Fordson tractor had a water bath air cleaner. By the 1940s, oil bath designs had displaced water bath designs because of better filtering performance. [9]
Bulk solids handling involves the transport of solids (mechanical transport, pneumatic transport) which may be in a powder form. Many industries are handling bulk solids (mining industries, chemical industries, food industries) which requires the treatment of air streams escaping the process so that fine particles are not emitted, for regulatory reasons or economical reasons (loss of materials). As a consequence, air filters are positioned at many places in the process, especially at the reception of pneumatic conveying lines[10] where the quantity of air is important and the load in fine particle quite important. Filters can also be placed at any point of air exchange in the process to avoid that pollutants enter the process, which is particularly true in pharmaceuticals and food industries. The physical phenomena involved in catching particles with a filter are mainly inertial and diffusional[11]
Under European normalization standards EN 779, the following filter classes were recognized:
| Usage | Class | Performance | Performance test | Particulate size approaching 100% retention |
Test Standard |
|---|---|---|---|---|---|
| Coarse filters
(used as Primary) |
G1 | 65% | Average value | >5 μm | BS EN779 |
| G2 | 65–80% | Average value | >5 μm | BS EN779 | |
| G3 | 80–90% | Average value | >5 μm | BS EN779 | |
| G4 | 90%– | Average value | >5 μm | BS EN779 | |
| Fine filters
(used as Secondary) |
M5 | 40–60% | Average value | >5 μm | BS EN779 |
| M6 | 60–80% | Average value | >2 μm | BS EN779 | |
| F7 | 80–90% | Average value | >2 μm | BS EN779 | |
| F8 | 90–95% | Average value | >1 μm | BS EN779 | |
| F9 | 95%– | Average value | >1 μm | BS EN779 | |
| Semi HEPA | E10 | 85% | Minimum value | >1 μm | BS EN1822 |
| E11 | 95% | Minimum value | >0.5 μm | BS EN1822 | |
| E12 | 99.5% | Minimum value | >0.5 μm | BS EN1822 | |
| HEPA | H13 | 99.95% | Minimum value | >0.3 μm | BS EN1822 |
| H14 | 99.995% | Minimum value | >0.3 μm | BS EN1822 | |
| ULPA | U15 | 99.9995% | Minimum value | >0.3 μm | BS EN1822 |
| U16 | 99.99995% | Minimum value | >0.3 μm | BS EN1822 | |
| U17 | 99.999995% | Minimum value | >0.3 μm | BS EN1822 |
European standard EN 779, on which the above table is based, remained in effect from 2012 to mid-2018, when it was replaced by ISO 16890.[12]
