If you are a subcontractor's what would you do when it comes to hazards or risk that your management team did not cooperate?

If a risk materialized into a major hazardous event or ( a crisis) then crisis management comes into place.

on the time of intense difficulties arising from the crisis and its consequences the management efforts should focus on three pillars to mitigate the problem prevent any further escalation and reduce the outrage of people involved through clear and simple communication messages. 

However the details of how could this be implemented depends on the nature of the hazard you are dealing with.