On Friday, August $23,2016,$ a construction worker fell $55$ floors to his death while working on what will become Toronto$$s tallest condominium building. Despite a variety of safety precautions, this type of incident is not uncommon in the construction industry. Three days earlier, on Tuesday, August $20,2016,$ a $26-$year$-$old construction worker in Las Vegas, Nevada also died in a fall from a building under construction.

What would be an example of the fourth level of defence from the Swiss cheese model, which might have prevented this fatality?

Question $4$ options:

safety training

a strong safety culture

a safety$-$conscious supervisor

rails along the edge of open floors