From the perspective of an offshore resident, our Planned Maintenance System requires regular inspections of fixtures and fittings both on and in the vicinity of the helideck. The HLO also carries out a FOD check as well as a visual inspection of the net prior to operations, and as has already been mentioned, the whole sphere of helicopter operations is subject to a periodic audit.
I've no doubt that should a crew have any concerns about the integrity of our helideck, we'd hear about it in short order, and we have a vested interest in maintaining our primary means of getting off.