Test parameters | Main influence | Typical failure results |
High relative humidity | Moisture absorption or adsorption; expansion; mechanical strength reduction; chemical reaction; corrosion; electrical corrosion; the conductivity of the insulator increases. | Physical damage, insulation failure, mechanical failure. |
Low relative humidity | Drying; embrittlement; reduced mechanical strength; shrinkage; increased wear between moving contacts. | Mechanical failure, cracking. |
Damp Heat Storage
The damp heat steady state test is primarily intended for component type specimens, to determine, in an accelerated manner, the resistance of specimens to the deteriorative effects of high temperature/humidity and cold conditions. The advantages of this method are its rapidity of application and that it utilizes convection heating; it therefore minimizes degradation due to radiation from heated surfaces. This test method of Third-party testing is not intended for the determination of long-term degradation under humid environments (at least not until the specimen shows signs of decomposition).
Damp Heat Test Standard
IEC 60068-2-78: Environmental testing - Part 2-78: Tests - Test Cab: Damp heat, steady state
GB/T 2423.4: Environmental testing for electric and electronic products - Part 2: Test methods - Test Db: Damp heat, cyclic (12 h + 12 h cycle)
IEC 60068-2-30: Environmental testing - Part 2-30: Tests - Test Db and guidance: Damp heat, cyclic (12 h + 12 h cycle)
GB/T 2423.50: Environmental testing for electric and electronic products - Part 2: Test methods - Test Z/AD: Damp heat (steady-state)
IEC 60068-2-67: Environmental testing - Part 2-67: Tests - Test Db: Damp heat, cyclic (12 h + 12 h cycle)
GB/T 2423.40: Environmental testing for electric and electronic products - Part 2: Test methods - Test Dd: Damp heat, cyclic (12 h + 12 h cycle)
IEC 60068-2-66: Environmental testing - Part 2-66: Tests - Test Db and guidance: Damp heat, cyclic (12 h + 12 h cycle)
MIL-STD-810H: Test Method Standard for Environmental Engineering Considerations and Laboratory Tests - Method 507.6: Damp heat
MIL-STD-883K: Test Method Standard for Microcircuits - Method 1011.13: Damp heat (steady-state)
MIL-STD-202G: Test Method Standard - Electronic and Electrical Component Parts - Method 103: Moisture resistance (damp heat)
GJB 150A: Environmental Test Methods for Military Equipment - Part A: Damp heat test
GJB 360B: Environmental Test Methods for Military Equipment - Part B: Damp heat test
GJB 548B: Environmental Test Methods for Military Equipment - Part B: Damp heat test
GB/T 28046.4: Road Vehicles - Environmental Conditions and Testing for Electrical and Electronic Equipment - Part 4: Damp heat test
ISO 16750-4: Road Vehicles - Environmental Conditions and Testing for Electrical and Electronic Equipment - Part 4: Damp heat, steady state
YD/T 2379: Technical Requirements and Test Methods for Telecommunications Equipment - Part 4: Damp heat test
ETSI 300 019-2: Environmental Engineering (EE) - Environmental Conditions and Environmental Tests for Telecommunications Equipment - Part 2: Damp heat
GR-63: Generic Requirements for Network Telecommunications Cabinets, Electrical, and Environmental: Damp heat
GR-487: Generic Requirements for Telecommunications Data Center Equipment and Spaces: Damp heat
These standards outline the test methods and procedures for evaluating the performance and reliability of products under damp heat conditions.