safety certifications for plant start up

[indianindian]

dear friends,

i want to know about the safety certifications for a plant startup. I heard that there are 4 types of certification
like A1, A2, A3, A4.

kindly explain about this & provide me the guidelines & details of the same.

regards

[ruudoleo]

i googled a bit as i was also puzzled and found following info

EN60950 EU low voltage directive amendments is now replaced with EN60950-1 2nd edition

http://www.i-spec.com/IEC_60950/european_union950.html

http://www.itesafety.com/en_e3.pdf

i doubt this is what you search for but at least you find here the EN60950 standard for CE certification