Home > News & Information > Lenpure News >

News & Information

Climatic chambers for test standard ASTM D4587

Climatic chambers for test standard ASTM D4587
This practice covers the selection of test conditions for accelerated exposure testing of coatings and related products in fluorescent UV and condensation devices conducted according to practices G151 and G154. This practice also covers the preparation of test specimens, and the evaluation of test results. Table 1 describe commonly used test conditions. This standard needs a climatic chamber--UV-lamp weathering test chamber.
The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. This standard does not to purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

The cycles described are not listed in any order indicating importance, and are not necessarily recommended for the applications listed. Additional exposure cycles are described in Practice G154. The irradiance set point given is typical for devices operated without irradiance control. Other irradiance levels may be used, but must be described in the report.
Previous editions of practice D4587 contained non-mandatory irradiance set points in Table 1 that were commonly used in the industry. The previous set points were 0.72 and 0.77 W(㎡.nm) at 340nm for UVA 340 lamps. The measurement data used to establish these set points were inaccurate, due to an error in calibration on the part of one manufacturer.
The definitions given in Terminology G113 are applicable to this practice. The ability of a paint or coating to resist deterioration of its physical and optical properties caused by exposure to light heat, and water can be very significant for many applications. This practice is intended to induce property changes associated with end-use conditions, including the effects of sunlight, moisture, and heat.
The exposure used in this practice is not intended to simulate the deterioration caused by localized weather phenomena such as atmospheric pollution, biological attack, and saltwater exposure. Cautions---Variation in results may be expected when different operating conditions are used. Therefore, no reference to the use of this practice shall be made unless accompanied by a report prepared according to Section 10 that describes the specific operating conditions used. Refer to Practice G151 for detailed information on the caveats applicable to use of results obtained according to this practice.
The spectral power distribution of light from fluorescent UV lamps is significantly different from that produced in light and water exposure devices using other light sources. The type and rate of degradation and the performances rankings produced in exposures to fluorescent UV lamps can be much different from those produced by exposure to other types of laboratory light sources.
Interlaboratory comparisons are valid only when all laboratories use the same design of fluorescent UV device, lamp, and exposure conditions. Reproducibility of test results between laboratories has been shown to be good when the stability of materials is evaluated in terms of performance ranking compared to other materials or to a control. Therefore, exposure of a similar materials of known performance (a control) at the same time as the test materials is strongly recommended. It is recommended that at least three replicates of each material be exposed to allow for statistical evaluation of results.
Test results will depend upon the care that is taken to operate the equipment according to Practice G154. Significant factors include regulation of line voltage, temperature of the room in which the device operates, temperature control, and condition and age of the lamps. All references to exposure in accordance with this practice must include a complete description of the test cycle used.
Use of fluorescent UV apparatus that conform to the requirements defined in Practices G151 and G154 is required to conform to this practice. Unless otherwise specified, the spectral power distribution of the fluorescent UV lamp shall conform to the requirements in Practice G154 for a UVA 340 lamp.


Locate the apparatus in an area maintained between 18 and 27℃ (65 and 80°F). Measure ambient temperature at a maximum distance of 150mm from the plane door of the apparatus. Control of ambient temperature is particularly critical when one apparatus is stacked above another, because the heat generated from the lower unit can interfere within the operation of the units above.
Place the apparatus at least 300mm from walls or other apparatus. Do not place the apparatus near a heat source such as an oven. Ventilate the room in which the apparatus is located to remove heat and moisture.
Warning--In addition to other precautions, never look directly at the fluorescent UV lamp because UV radiation can damage the eye. Turn the device off before removing panels for inspection.
Apply the coating to flat (plane) panels with the substrate, method of preparation, method of application, coating system, film thickness, and method of drying consistent with the anticipated end use, or as mutually agreed upon between the producer and user.
Panel specifications and methods of preparation include but are not limited to practices D609, D1730, or specification D358. Select panel sizes suitable for use with the exposure apparatus. For specimens coated on insulating materials, such as foams, quickly check the specimens during the condensation period to verify that visible condensation is occurring on the specimens. Perform this visual check once per week at least one hour after the start of condensation.
Coat test panels in accordance with Practice D823, then measure the film thickness in accordance with an appropriate procedure selected from test methods D1005, D1186, or D1400. Nondestrucive methods are preferred because panels so measured need not be repaired.
Prior to exposing coated panels in the apparatus, condition them at 23±2℃ and 50±5% relative humidity for one of the following periods in accordance with the type of coating:

For more details, please feel free to contact sales@lenpure.com
Please visit www.lenpure.com