27th May 2015
It is a requirement of the Indian authorities (Method 1 of IS 8747) that infant feeding bottles made from polycarbonate allow a minimum of 85% of light to be transmitted. This test must be done “in house” by the manufacturer. The test described uses light source C and an integrating sphere.
CIE standard illuminant C is a colorimetric illuminant, representing daylight with a correlated colour temperature of 6774K, defined by the CIE in terms of a relative spectral power distribution.
The percentage of light transmitted by a sample is the light transmitted by the sample divided by the light transmitted by the blank or reference and should not be affected by the light source, provided that a baseline is first stored.