Heat Stress Calibration
CIHE calibrates and verifies the performance of heat stress monitors using best practice metrology methods. Our procedures are designed to maximize the repeatability, reproducibility, and accuracy of your heat stress monitor. A Tenney Junior environmental chamber and reference thermometer our used in our heat stress monitor calibration system.
Tenney Jr. Enviornmental Chamber Construction
- Features vapor-tight, continuously welded stainless steel interiors.
- Structural reinforcement is used at all critical points.
- A combination of fiberglass and polyurethane insulation surrounds the temperature chamber to maximize insulating characteristics, thus ensuring minimal thermal transfer.
Control Tolerance
- ±0.3°C after stabilization
Resolution
- Setpoint and chamber temperature are displayed with 0.1°C or 0.1°F resolution.
Sensors
- A platinum RTD sensor measures temperature in the chamber.
- The sensor provides excellent control and display accuracy with minimum maintenance.
Refrigeration System
- Tenney Hermeticool®: air-cooled, readily accessible hermetic system uses accurately calibrated capillary tubes rather than mechanical expansion valves.
- This simplifies the system and reduces the likelihood of leaks.
Heating System
- Low-mass nichrome, open wire heating elements are used to reduce thermal lag and provide rapid response to instrument demand.
- The heating elements are isolated from the workspace to reduce radiant influence on the test item.
Conditioning System
- Uniform conditions are assured through the use of a vertical-down recirculating conditioning stream.
- The system draws air from the bottom of the workspace, conditions as required, then discharges the air through a grille at the ceiling level.
- The compact design of the conditioning plenum allows the test chamber to offer a larger proportional area of interior volume to exterior volume than afforded by conventional chamber.
Door
- Since the temperature chamber is continuously welded, the door remains as the final sealing surface to maintain atmosphere integrity.
- The door is equipped with double gaskets that trap air for the purpose of insulation.
