Filter
Contents |
[edit] What does filter mean?
The word 'filter' is both a verb, meaning the act of passing through something or moving slowing in a certain direction and a noun, referring to a system by which an object moves in a certain direction or the object through which something passes. A filter is usually an object that can separate certain elements from one another, often removing unwanted parts or impurities such as particles from materials, liquids or gas that pass through, this can also be used in electronics as well as digital systems.
In the design and construction of buildings and cities there are two common uses of the term, the first relatively simple application and the second with a wider set of applications.
In city, urban or traffic planning and management a filter may be used to refer to a system of traffic management, where by vehicles filter left or right within a road junction or traffic light or signage system. The term can also be used in the design of pedestrian traffic systems in buildings or the urban realm, also referred to more generally as people-movement (as in crowd flow, way-finding and evacuation) where route-ways, layout, signage or indicators act as filters to encourage pedestrians in one direction or another. This theme touches on a number of design and research areas such as crowd flow, way-finding, evacuation, place-making, and urban simulation.
In terms of building design and construction, filters are often key component parts of building service systems; in air systems, they filter particles, in water systems, they remove minerals, and in gas systems, they remove solid particles from the flow. Filters are also used in electronic systems to remove unwanted frequencies from electric or other signals.
Filters are also common place component parts of domestic appliances such as washing machines, dishwashers, tumble driers, steamers, fryers etc. Filters in each of these systems vary in their design, task, function, longevity, and maintenance requirements, and there are likely to be classification systems to describe their type and the substances they can actively separate, as well as their class, which describes the grade of material they can filter and their capacity to remove and effectively absorb unwanted elements.
[edit] Types of filters
[edit] Air filters
- HEPA filters.
- Washable filters.
- Electrostatic filters.
- UV light filters.
- Media filters.
- Spun glass filters.
- Pleated filters.
[edit] Water filters
- Mechanical Filters.
- Absorption Filters.
- Sequestration Filters.
- Ion Exchange Filters.
- Reverse Osmosis Filters.
[edit] Gas filters
- Types
- Class 1-3
[edit] Electronic filters
- Passive filters
- Active filters
- Analog filters
- Digital filters
- High-pass
- Low-pass
- Band-pass
- Band-stop (band-rejection; notch)
- All-pass.
- Discrete-time (sampled)
- Continuous-time
- Linear
- Non-linear
- Infinite impulse response (IIR type)
- Finite impulse response (FIR type)
[edit] Related articles on Designing Buildings
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
Construction Management, 8 July
NEETs crisis drives interest in trades, but apprenticeships barriers remain.
Passive fire protection webinar
MEP services penetration seals.
Where its at podcast (and video) - The role of the Architectural Technologist as an Expert Witness.
More than 200 remarkable buildings added to SAVE’s Buildings at Risk register.
Government scraps pre-application consultation for Nationally Significant Infrastructure Projects.
Historic England and infrastructure
New projects offer opportunities for the historic environment and local communities.
Construction Management, 2 July
Construction deaths halve in two years.
Green Book changes to drive investment in all parts of UK.
Minimum energy efficiency standards (MEES)
CIAT briefing on response to consultations for privately rented non-domestic properties.
Connect, collaborate, shape the future
Registration now live for UK Construction Week Birmingham.
CIOB announces Saul Humphrey FCIOB as new President for 26/27 term.
A quick, simple, and zero-bills solution to prevent overheating.


















Comments
[edit] To make a comment about this article, or to suggest changes, click 'Add a comment' above. Separate your comments from any existing comments by inserting a horizontal line.