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Environmental Test Chambers

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 Associated Envoronmental Test Chambers, a BMA Company

Manufactured & Serviced in Avon, MA USA


Environmental Test Chambers, Ovens, Walk-In Rooms, Thermal Shock

 and Salt Spray Chambers.


Associated Environmental Systems (AES) designs and manufactures standard and customized environmental chambers. Our products vary in size from small bench top chambers to very large walk-in environmental rooms. Whether you are looking for off-the-shelf or unique solutions, we can meet your needs.

AES is an industry leader with an installed base of over 100,000 chambers worldwide. The robustness and reliability of our products is shown by the fact that some AES chambers that were installed in the 1970s are still in use today.

AES chambers are used to test and manufacture items across a broad spectrum of temperatures and humidity. Our chambers are widely used for many applications. A few examples are: electronics, aerospace, defense, scientific and medical laboratories, manufacturing research and development.

AES design, engineering, and manufacturing teams work closely together to incorporate new technologies and evolve our state-of-the-art product lines. Our goal is to ensure consistent product excellence coupled with conformance to national and international standards.

AES is a BMA company. For over 25 years we have enjoyed an outstanding reputation for responsiveness and quality. The availability of support and spare parts helps our customers get the most out of their initial investment. We also offer flexible payment plans including leasing. Contact us to discuss your needs.


 Environmental Test Chambers Index

CO2 / LN2

LH Series (Economy)

Laboratory Ovens

Mechanical Refrigeration Chambers

Salt Spray/Fog Chambers

Temperature / Humidity Chambers

Thermal Shock Chambers

Special Chambers

Walk-In Rooms


 CO2 / LN2 Chambers


Model / Data Link

Description / Features


BD-100 Series


BDE-100 Series


SD-100 Series


SD-600 Series


1/2 cubic Feet


64 cubic Feet

Standard features on all AES Chambers, including CO2/LN2 Chambers are:

  • Forced air circulation systems maintain precise temperatures and use a fan powered by a direct drive, heavy duty electrical motor that is externally mounted with an integral stainless steel shaft.

  • Heating systems are located in a plenum so that test items are not subject to direct radiation. Open wire nichrome resistance elements combine maximum heat transfer with rapid response time and long operating life.

  • Fail-safe high-temperature control guards against damage due to abnormal high temperature extremes.

  • Fusible thermal links guard against temperatures exceeding the upper design limits of the equipment.

  • Non-magnetic welded type 304 stainless steel inner chambers.

  • Exterior cabinet of reinforced cold rolled steel with fully-welded construction.

  • Textured enamel finish for a laboratory look.

  • Most doors are combination hinged and removable for easy access access and modification.

  • Doors are gasketed with silicone to handle the expanded range of temperatures.

  • Door latches have a quick-action cam mechanism for positive closure.

  • High density low K factor, non-settling fiberglass insulation is standard in walls and doors.


Economy Temperature / Humidity


Model / Data Link

Description / Features

LH Series


Prices start at under $6,000

LH Series

  • Self-contained systems use a two-channel microprocessor digital controller.

  • Easy to operate.

  • Standard units are available from stock in three (3) sizes: 1.5 cubic feet, 5.8 cubic feet, and 10 cubic feet.

  • Temperature range is 0C to +94C with an optional temperature range of -20C to +94C.

  • Humidity range is 20% to 98% 2 RH.


Laboratory Ovens


Model / Data Link

Description / Features


Laboratory Ovens

BD-900 Series


Mechanical Refrigeration Chambers


Model / Data Link

Description / Features

Bench Top SD Series

Bench Top Model




Floor Model FD Series

Floor Model


SD Series



FD Series


Simulate high and low temperature environments in Associated Environmental Systems bench top or floor model test chambers.

  • Working volume from 2 to 64 cubic feet.
  • Conform to commercial and military standards for low temperature tests.
  • Self-contained single-stage refrigeration systems support low temperatures to -35F/-37C.
  • Two-stage cascade refrigeration systems support low temperatures to -100F/-73C. The two separate closed refrigerant circuits each use a different refrigerant with its own compressor

Standard features include:

  • High performance programmable controller with RS232 Interface
  • Stainless steel welded interior
  • Adjustable CE-approved low temperature fail-safe
  • 2" diameter access port and plug
  • Multipane viewing window
  • Internal light with external switch

Optional features include:

  • IEEE-488 computer interface
  • CO2 or LN2 for fast pull-down
  • Durable floor stand with casters
  • Additional ports
  • Programmable chart recorders


Salt Spray / Fog Chambers


Model / Data Link

Description / Features

 MX-9200 Series

Corrosive atmosphere chambers subject test items to corrosion without introducing other contaminants into the test area.

Associated Environmental Systems' salt spray chambers are entirely self-contained. The basic chamber conforms to military specifications, including MIL-STD-810, and is also used for many commercial and ASTM specifications.

The MX-9200 corrosive atmosphere chamber:

  • Has a transparent Lucite test area that is impervious to corrosion.

  • Provides continuous direct visual observation of the test item.

  • Contains thermostats and metallic items made of Monel to avoid transference and minimize corrosion.

  • Provides lucite rods to hang or support items within the test area.

  • Performs continuous unattended tests for up to 72 hours. This period may be extended by adding an external storage tank, a tower level control and a salt solution reservoir level control to automatically refill the system.

A high reliability thermostatic temperature controller maintains the salt solution at a preset controlled temperature in a reservoir within the double wall construction. The salt solution is introduced into the chamber through an atomizing nozzle. The nozzle can be calibrated by AES to perform to MIL-STD-19500B, paragraph 40.8 and other specifications. This specification requires that a salt residue be deposited on the specimens, in addition to generating salt fog atmosphere.

The preparation of a salt solution consists normally of sodium chloride containing as a dry compound not more than 0.1% of sodium iodide and not more than 0.2% of total impurities. This solution is prepared by dissolving five parts by weight of salt in 95 parts by weight of distilled water. It is important to maintain this solution at a specific gravity of from 1.023 to 1.037. The solution is maintained at a controlled temperature of 95F by the chamber's own integral temperature control system (temperature is adjustable).


 Special Chambers

Associated Environmental Systems will design and build custom test chambers to support your specific requirements including, but not limited to:

  • Non-standard sizes

  • Special temperature ranges

  • Unusual humidity ranges

Our team of experienced engineers has worked successfully with many government organizations, academic institutions, and commercial companies to provide environmental test chambers for unique testing situations.

Contact us to discuss your requirements.

Special ChamberSpecial ChamberSpecial ChamberSpecial Chamber


 Temperature / Humidity Chambers


Model / Data Link

Description / Features


Bench Top BDH Series

Bench Top Model




Floor Model HD Series

Floor Model


Bench Top

BHD series  



Floor Models

HD Series  



Economy Models

LH Series  


Associated Environmental Systems supplies Temperature/Humidity Chambers to program controlled conditions of combined temperature and relative humidity.

All chamber components offer maximum resistance to the corrosive effects of moisture combined with extreme conditions. Consult the AES design engineering services for special temperature and humidity conditions.


BHD-500 and BHD-200 Series

The BHD-500 Series use a single-stage mechanical refrigeration system that can produce dry bulb temperatures down to 35F/-37C.

The BHD-200 Series produces dry-bulb temperatures down to -100F/-73C.

  • Non-corrosive, stainless steel finned heaters are baffled to eliminate direct radiation to the test items at high temperatures of up to +350F/+177C.
  • Chamber liners are hermetically sealed and made of heliarc welded stainless steel.


Thermal Shock Chambers


Model / Data Link

Description / Features


SM-2100 Series


2 cubic Feet


8 cubic Feet

Thermal Shock Chambers make it possible to automatically and repeatedly transfer a test item from a hot environment to a cold environment or from a cold environment to a hot environment. This process is defined as true thermal shock and it is different from thermal cycling, where the specimen is introduced into the chamber and the chamber temperature is then cycled. A true thermal shock chamber can achieve a 265C temperature variation rapidly, while thermal cycling may take hours to ramp up or down.

Associated Environmental Systems offers Thermal Shock Chambers that support true thermal shock testing.

Two Station Chambers provide an upper compartment for a heated environment and a lower compartment for a cold environment.

Three Station Chambers contain an additional middle compartment that is exposed to room ambient (ambient dwell) and is enclosed with expanded metal.

Each chamber contains a specimen holding basket (transport carriage) pneumatically operated from a compressed air source.



Walk-In Rooms



Description / Features


Walk-In Room


5' x 5'


30' x 30'

Associated Environmental Systems offers a range of prefabricated, tight-tolerance environmental rooms that are easy to ship and install. Major features include:

  • Forced air circulation systems distribute air evenly and constantly recirculate it, maintaining uniform and accurate temperatures and humidity.

  • Temperature Ranges are from -73C (-100F) to +85C.

  • Refrigeration system meets the room's load demand and operates continuously in cooling mode. Single-stage mechanical units operate at -35C and above and two-stage cascade units at below -35C.

  • Electric heating system provides very accurate and straight line control of temperatures. System is reliable and has a long life.

  • Humidity System choices are the conditioned fine Mist System or the Steam Generator System. Different ranges are available including special dehumidity ranges to 5% RH.

  • Prefabricated room construction consists of modular, sandwich-type panels with a metal skin inside and outside. Panels are easy to ship and assemble.

  • Multipane viewing windows can be ordered in custom sizes.

  • Incandescent or fluorescent lighting is vapor-proofed and sealed.

  • Instrumentation consists of single or two-channel microprocessor programmers with an accuracy of .25C or better at the sensor. Other options include: RS-232C, RS-422A, IEEE-488 interface.

  • Safety standard is a redundant control circuit with its own controller and failsafe contactor. Many other options are available.

Room Construction
Rooms are constructed of prefabricated metal tongue and groove sectional panels. An assembled room has continuous steel perimeters to hold panels tightly in place.

Panel features include:

  • 100% insulation

  • Light weight for easy handling average weight of the largest panel is 84 lbs.

  • Alignment pins for accurate fit.

  • Steel straps connect locking arms with locking pins on opposite sides of panels.

  • Cam-actuated locks ensure tight fits and accommodate frequent assembly/disassembly for relocating or enlarging the room.

Viewing Windows
The standard multipane window has a 14" by 23" viewing area. Thermostatically controlled heater wire in the window casing minimizes condensation and frost formation on the window surface. Custom size windows are available.

All lighting fixtures are vapor proof and sealed. Both incandescent and fluorescent lighting fixtures are available.
Incandescent lighting is recommended for high temperature units operating above +110F and low temperature units operating below 0F.

Forced Air Circulation Systems
All rooms incorporate forced air circulation. Differences in the size of the chamber and its internal configuration are accommodated by various airflow patterns, including horizontal, vertical, or a combination of both. These provide an even distribution of air and tight temperature control. Noise is also a consideration.

The air circulation systems use external heavy duty motors to distribute air evenly and constantly recirculate it, maintaining uniform and accurate temperatures and humidity. The high quality motors have internal cooling fans, protectors, and stainless steel shafts. Aluminum or stainless steel squirrel cage blowers circulate the air. All mixing is within a plenum that is external to the room work area.

In tight tolerance environmental rooms, air must be evenly distributed and constantly recirculated at a higher than normal rate in order to maintain uniformity and accuracy. A portion of one wall of the room is devoted to a conditioning plenum. Air is drawn into the lower part of the plenum through a set of cleanable filters, across an evaporator coil and vertically across electric heaters. The air then enters centrifugal fans and is discharged into a perforated ceiling plenum. The air flows vertically downward in the room and is returned horizontally through the cleanable filters to the wall plenum.

Electric Heating System
The combination of airflow, instrument response, and fast-reacting heaters provides very accurate and straight line control of temperatures.

Air is passed over the fast response, low watt density heaters with ceramic cores. This type of system provides very accurate air and humidity control. A separate instrument precisely controls the heat level.

The heating systems have a long life and are very reliable, with no down time.

Instrumentation consists of either single or two-channel microprocessor programmers with an accuracy of .25C or better at the sensor. The sensors are fast acting 100 Ohm. platinum type.

Other options include: RS-232, IEEE-488 interface.

Standard is a redundant control circuit with its own controller and failsafe contactor. To prevent thermal runaway, the safety control shuts off power to the heater circuit and the circulation blowers continue to distribute heat within the room. This feature is particularly important if there are heat-generating items in the room. When the temperature goes down, the safety control closes and power is restored to the heaters.

Other available safety options are: High Temperature Safety with Complete Shut Down of Room with Manual Reset and Visual Indication, Low Temperature Safety with Complete Shut Down of Room with Manual Reset and Visual Indication, Both High and Low Temperature Safety with Manual Reset on Both and Visual Indication, Audible Alarm, and Remote Station Alarms.

Electrical Requirements
Standard power requirements include 208V 3PH 60HZ, 220/240V 3PH 60HZ, 460V 3PH 60HZ, 208/220V 1PH 60HZ. Other power requirements are available upon request.

Temperature Ranges
Various ranges can be provided, including fast change rates with your product load. Ranges from -73C (-100F) to +85C are available.

Walk-in Room

Standard ranges available are: 20% to 95% 5% RH. 10% to 98% 2% RH. Different ranges available including special dehumidity ranges to 5% RH.

Humidity System
Two Humidity systems are standard:

  • Fine Mist System is recommended when doing continuous testing with high live loads.

  • Steam Generator System is recommended for rooms being used for low and high humidity testing within the range of +40F to +130F.

The conditioned Fine Mist System uses your local water supply. Steam is created within a plenum outside the room area by spraying a fine mist over a stainless steel sheath-type heater. The circulation system carries this steam throughout the room.

The Steam Generator System uses an external self-contained steam generator with all necessary safety and water level controls to provide humidities to saturation point within the room.


Walk-in Room      Walk-in Room

Refrigeration Systems
AES supplies a refrigeration package that supports the load demands of the Walk-In Environmental Room.

  • Single-stage mechanical refrigeration systems operate at -35C and above.

  • Two-stage cascade refrigeration systems (air cooled or water cooled) operate below -73C.

All systems:

  • Operate continuously in cooling mode.

  • Provide a hot gas by-pass system to automate capacity reduction when the room is at the set point temperature.

  • Are constructed with high quality components including: liquid line solenoids, liquid sight glass, dryers, strainers, and TX valves.

  • Contain Copeland semihermetic (or equal) compressors.

  • Contain Penn (or equal) controls.

  • Comply with ASHRAE guidelines for piping and rating.

  • Are factory-assembled and tested.

  • Are simple to maintain because components are easily accessible and clearly labeled.

Up to 5 HP units can be mounted on the roof of the room. Larger units are installed on the floor next to the room.

Comprehensive piping diagrams, schematics, and charging data are available.





 Last Updated: February 16, 2017

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An Electro Mechanical Research and Development (EMRAD) Corporation, Company


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