Dear Mr. Kailash
As per my knowledge what we should ensure when comes to Safety Net is as follows:
1. There should be test certificate of Safety Net from the manufacturer. This should clearly speak about the expiry date of the same, which standard its confirmed to and SWL. Also you should do the care and maintenance of the Safety Net as per the manufacturer guidelines.
2. You should have internal checklist to check the condition of Safety Net on periodical basis and the net should be taken out of use in case found any damages.
Now regarding the test certificate you mentioned. As you said, it is based on IS 5175. This standard referees to - Polypropylene ropes (3-strand hawser-laid and 8-strand-plaited). So in this case I am not sure about the reliability of this certificate, as this standard is not corresponding to the make of Safety Nets. What is the make of this safety net? Does the certificate covers the name of the manufacturer?