Should there be re-occurrence of the same incident, what will be your next move as an H&S Manager?

First, full investigation have to be conducted to identify the root causes why the incident had re-occurred, 

Second, review the recommendations from previous incident and verify whether all were appropriately addressed  or there are still vital measures not captured or addressed during the investigation process.

Third, present the findings to top management to inform them and accord full support to ensure all recommendations/mitigation measures are appropriately addressed by the concerned parties as per the target completion date.

Fourth, register all recommendations in the tracking register and monitor/track corrective actions done vs target  completion date 

You have to revised your HSE Management system, e.g. Risk Management, Competency of your trainer and most importantly is to be vigilant on site in studying the trend or working culture of the mass or the individual group.