ASTM Standard

Since the very beginning of CPSA, the society recognized that lightfastness was the single most important quality issue to colored pencil artists. Knowing how a medium will withstand the test of sun and time is important to every dedicated artist. Because of this, CPSA worked diligently in conjunction with ASTM International (formerly American Society for Testing and Materials), colored pencil manufacturers, and art conservators to create D6901, the Standard Specification for Artists鈥 Colored Pencils, which was published in 2003.

D6901 uses two types of lightfast testing, a sunlight test and a xenon arc test, to simulate the effects that prolonged sun exposure will have on a colored pencil. With the results of these tests, a colored pencil can then be accurately placed into a lightfastness category. Lightfastness categories are I, II, III, IV, and V with I being the best (very lightfast) and V being the worst (fugitive/not lightfast). Only pencils with lightfastness ratings of either I or II can be labeled as complying with the standard. For an entire line of colored pencils to be labeled as D6901 compliant, every pencil must have a lightfast rating of either I or II.

Unfortunately, complying with the standard is not mandatory. We urge artists to contact companies directly with their concerns about quality issues such as lightfastness. Artists must make their voices heard if they want to have high quality, lightfast materials available.

LF Testing by CPSA