Dear Mrityunjay,
There are a few things to be noted here:
a) Death of a worker happened while on duty.
b) The death happened in the course of his work. I do not know whether it can be classified as an "occupational hazard." However, it was not due to some chronic disease like heart disease, etc.
c) The post-mortem report also shows that death happened due to suffocation, and suffocation happened during the work.
Therefore, prima facie, we can infer that the death of the workman is attributable to the employment. But then why has your inquiry committee given any contrary report? Did he fail to observe any safety precautions? If yes, then what was that? What kind of safety training was he given? When was it given, and do you have evidence of the training? What about your SOPs? Did his action go against any laid-down SOP?
ISO certification has nothing to do with the workman's compensation, please note.
Have the workman's kith and kin approached you for compensation? If yes, did you turn down the compensation? I recommend you keep the labor officer of your area in the loop. Have you sent a copy of the findings of the inquiry report to the labor officer? Has he endorsed the findings?
All these questions are from a legal point of view. From the organization's culture point of view, I recommend you give his dependents the legally admissible dues. If you fail to do that, then employees' perceptions towards the company will change, and they will start looking down upon the management.
You may not pay the compensation provided that the worker had failed to observe the safety precautions or there was evident transgression of the laid-down SOP. In such a case, it may send a signal to one and all on how important the safety guidelines are and what happens when workers do not observe them.
Thanks,
Dinesh V Divekar