What is the difference between ASTM G154 and G155?

 

ASTM G154 is a standard test method for fluorescent ultraviolet (UV) lamp apparatus for exposing nonmetallic materials. This standard specifies the conditions for exposing specimens using fluorescent ultraviolet lamps in a controlled laboratory environment. The test simulates the UV radiation, heat and humidity of natural sunlight. ASTM G154 can be used to evaluate the weathering resistance of various non-metallic materials, such as plastics, rubber, coatings, etc.
 

 

ASTM G155 is a standard test method for fluorescent ultraviolet (UV) lamps and water spray equipment for exposing materials. This standard specifies the conditions for exposing specimens using fluorescent ultraviolet lamps and water spray in a controlled laboratory environment. This test can simulate environmental factors such as ultraviolet radiation under natural sunlight, water and rain erosion and humidity, and is closer to real weather aging conditions. ASTM G155 can be used to evaluate the weathering resistance of various materials, such as coatings, metals, plastics, rubber, textiles, etc.

 

Therefore, the main difference between ASTM G154 and G155 is the environmental conditions under which the specimens are exposed. ASTM G154 uses only fluorescent UV lamps to expose specimens, while ASTM G155 uses both fluorescent UV lamps and water spray equipment to expose specimens to an environment closer to real weather. Therefore, ASTM G155 is more suitable for testing materials that require more realistic weathering conditions, while ASTM G154 is more suitable for weathering testing of general materials.

 

It should be noted that no matter which test method is used, the test should be carried out under the conditions specified in the standard, and the influence of external factors should be controlled to ensure the accuracy and repeatability of the test results.