Environmental chamber
Encyclopedia
An environmental chamber is an enclosure used to test the effects of specified environmental conditions on biological items, industrial products, materials, and electronic devices and components. Environmental chambers help evaluate product quality and reliability, and identify manufacturing flaws and weaknesses. By simulating environmental conditions within a contained space, the chamber offers test results that can show the process of product decay and degradation and help predict the potential lifespan of a product or material.
Such a chamber can be used:
These conditions may include:
Manufactured samples, specimens, or components are placed inside the chamber and subjected to one or more of these environmental parameters to determine reliability or measure after-effects such as corrosion. In the case of machinery such as internal combustion engines, byproducts such as emissions are monitored.
An environmental chamber can be a small room used both to condition test specimen
s and to conduct the test. It can be a smaller unit that's used for conditioning test items. Also, some chambers are small enough to be placed onto a universal testing machine
or other test apparatus.
Many chambers are set at a certain set of conditions. Others can be programed to cycle through specified sequences of conditions.
As with the wide variance in size, a number of user control options are available, ranging from simple analog indicators up to more modern digital readouts with LCD displays. Chambers may be computer programmable, and networked or Web-enabled test chambers are also available.
Such a chamber can be used:
- as a stand-alone test for environmental effects on test specimenSpecimenA specimen is a portion/quantity of material for use in testing, examination, or study.BiologyA laboratory specimen is an individual animal, part of an animal, a plant, part of a plant, or a microorganism, used as a representative to study the properties of the whole population of that species or...
s - as preparation of test specimens for further physical testPhysical testA physical test is a qualitative or quantitative procedure that consists of determination of one or more characteristics of a given product, process or service according to a specified procedure...
s or chemical testChemical testIn chemistry, a chemical test is a qualitative or quantitative procedure designed to prove the existence of, or to quantify, a chemical compound or chemical group with the aid of a specific reagent...
s - as environmental conditions for conducting testing of specimens
Overview
An environmental test chamber artificially replicates the conditions under which machinery, materials, devices or components might be exposed. It is also used to accelerate the effects of exposure to the environment, sometimes at conditions not actually expected.These conditions may include:
- extreme temperatures
- sudden and extreme temperature variations
- moisture or relative humidityRelative humidityRelative humidity is a term used to describe the amount of water vapor in a mixture of air and water vapor. It is defined as the partial pressure of water vapor in the air-water mixture, given as a percentage of the saturated vapor pressure under those conditions...
- electrodynamic vibrationVibrationVibration refers to mechanical oscillations about an equilibrium point. The oscillations may be periodic such as the motion of a pendulum or random such as the movement of a tire on a gravel road.Vibration is occasionally "desirable"...
s - electromagnetic radiation
- salt spraySalt spray testThe salt spray test is a standardized test method used to check corrosion resistance of coated samples. Coatings provide corrosion resistance to metallic parts made of steel, zamak or brass. Since coatings can provide a high corrosion resistance through the intended life of the part in use, it is...
- rainRainRain is liquid precipitation, as opposed to non-liquid kinds of precipitation such as snow, hail and sleet. Rain requires the presence of a thick layer of the atmosphere to have temperatures above the melting point of water near and above the Earth's surface...
- weatheringWeatheringWeathering is the breaking down of rocks, soils and minerals as well as artificial materials through contact with the Earth's atmosphere, biota and waters...
- exposure to sun, causing UV degradationUV degradationMany natural and synthetic polymers are attacked by ultra-violet radiation and products made using these materials may crack or disintegrate . The problem is known as UV degradation, and is a common problem in products exposed to sunlight...
- vacuumVacuumIn everyday usage, vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for "empty". A perfect vacuum would be one with no particles in it at all, which is impossible to achieve in...
Manufactured samples, specimens, or components are placed inside the chamber and subjected to one or more of these environmental parameters to determine reliability or measure after-effects such as corrosion. In the case of machinery such as internal combustion engines, byproducts such as emissions are monitored.
An environmental chamber can be a small room used both to condition test specimen
Specimen
A specimen is a portion/quantity of material for use in testing, examination, or study.BiologyA laboratory specimen is an individual animal, part of an animal, a plant, part of a plant, or a microorganism, used as a representative to study the properties of the whole population of that species or...
s and to conduct the test. It can be a smaller unit that's used for conditioning test items. Also, some chambers are small enough to be placed onto a universal testing machine
Universal Testing Machine
A universal testing machine, also known as a universal tester, materials testing machine or materials test frame, is used to test the tensile stress and compressive strength of materials...
or other test apparatus.
Many chambers are set at a certain set of conditions. Others can be programed to cycle through specified sequences of conditions.
Design
As test requirements may be relatively simple or complex, environmental test chambers vary widely in size, ranging from small units designed for placement on bench tops to large walk-in chambers. Test chambers generally have viewports or video feeds to allow for visual inspection of the sample during the test. Reach-in chambers provide an opening that technicians may use to handle test samples. Chambers providing interior visual lighting must take into account the heat generated and compensate accordingly.As with the wide variance in size, a number of user control options are available, ranging from simple analog indicators up to more modern digital readouts with LCD displays. Chambers may be computer programmable, and networked or Web-enabled test chambers are also available.
Test chamber standards
The Institute of Environmental Sciences and Technology is a leading source of standards for environmental test chambers. In addition, the following organizations provide guidance on environmental test chamber construction, temperature control standards, and engineering tolerances.- Air Conditioning, Heating and Refrigeration InstituteAir Conditioning, Heating and Refrigeration InstituteThe Air Conditioning, Heating and Refrigeration Institute , formed by a merger of the American Refrigerant Institute and the Gas Appliance Manufacturers Association , is a North American trade association of manufacturers of air conditioning, heating, and commercial refrigeration equipment...
(formerly the American Refrigerant Institute) - American Society of Heating, Refrigerating, and Air-Conditioning Engineers Air conditioning#American Society of Heating, Refrigerating, and Air-Conditioning Engineers
- ASTM InternationalASTM InternationalASTM International, known until 2001 as the American Society for Testing and Materials , is an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, and services...
- Underwriters LaboratoriesUnderwriters LaboratoriesUnderwriters Laboratories Inc. is an independent product safety certification organization. Established in 1894, the company has its headquarters in Northbrook, Illinois. UL develops standards and test procedures for products, materials, components, assemblies, tools and equipment, chiefly dealing...
- NSF InternationalNSF InternationalNSF International is an Ann Arbor, Michigan-based not-for-profit public health and environmental organization that provides standards development, product certification, auditing, education and risk management services.-History:...
- Factory Mutual
- Canadian Standards AssociationCanadian Standards AssociationThe Canadian Standards Association, also known as the CSA, is a not-for-profit Standards organization with the stated aim of developing standards for use in 57 different areas of specialisation...
- International Organization for StandardizationInternational Organization for StandardizationThe International Organization for Standardization , widely known as ISO, is an international standard-setting body composed of representatives from various national standards organizations. Founded on February 23, 1947, the organization promulgates worldwide proprietary, industrial and commercial...
See also
- Doriot Climatic ChambersDoriot Climatic ChambersThe Doriot Climatic Chambers are a pair of very large, highly specialized wind tunnels/environmental chambers located at the U.S. Army’s Soldier Systems Center in Natick, Massachusetts...
- Accelerated agingAccelerated agingAccelerated aging is testing that uses aggravated conditions of heat, oxygen, sunlight, vibration, etc. to speed up the normal aging processes of items. It is used to help determine the long term effects of expected levels of stress within a shorter time, usually in a laboratory by controlled...
- Environmental stress screeningEnvironmental stress screeningEnvironmental stress screening refers to the process of exposing a newly manufactured or repaired product or component to stresses such as thermal cycling and vibration in order to force latent defects to manifest themselves by permanent or catastrophic failure during the screening process...
- MIL-STD-810, DoD Standard for Environmental Engineering Considerations and Laboratory Tests
- Shelf lifeShelf lifeShelf life is the length of time that food, drink, medicine, chemicals, and many other perishable items are given before they are considered unsuitable for sale, use, or consumption...
- Standard conditions for temperature and pressureStandard conditions for temperature and pressureStandard condition for temperature and pressure are standard sets of conditions for experimental measurements established to allow comparisons to be made between different sets of data...
- Thermo-mechanical fatigue test
- Universal testing machineUniversal Testing MachineA universal testing machine, also known as a universal tester, materials testing machine or materials test frame, is used to test the tensile stress and compressive strength of materials...
- Weather testing of polymersWeather testing of polymersWeather testing of polymers is the controlled polymer degradation and polymer coating degradation under lab or natural conditions.Just like erosion of rocks, natural phenomena can cause degradation in polymer systems. The elements of most concern to polymers are Ultraviolet radiation, moisture and...