solved I need an explanation for this Social Science question to

I need an explanation for this Social Science question to help me study.

Our company does a lot of abrasive blasting. Industry wide, most companies have switched to blasting media that is 99.9% silica free, so by using the different types of media such as garnet or walnut shells, we are using a substitution control for the silica hazard. When we are abrasive blasting lead based paint, we use many controls to reduce exposure to lead. We use engineering controls with containments and dust collectors, as well as moving from dry blasting to vapor blasting where a small amount of water is added to the blast stream to keep particles from becoming airborne. We use administrative controls through training our employees in lead abatement and medical surveillance, as well as regulating the area we are doing the work in and performing area air monitoring. We then move to PPE by requiring employees to wear a blast hood with supplied air, and head to toe disposable clothing.