The distribution blocks, terminals which are used in low voltage and control gear assemblies generally certified only according to IEC 60947 - 7 - 1 which is infact only a terminal standard.
A distribution block in panel can face facts like short circuit case which is not considered or tested in IEC 60947 - 7 - 1. So these devices should be tested in a harmony of several standards.

Tekpan distribution products tested in international Dekra laboratories in Netherlands according to:

IEC 60947 - 7 - 1: Terminal tests including temperature rise and connections.
IEC 61439 - 1: 3 phase short circuit with stand tests lcw.
IEC 60947 - 1: Short circuit peak tests Ipk.

which provides maximum safety in panels.