This EPA diver is entering the water with extra safety precautions for the sampling effort.
Because of the polluted conditions, he is wearing a fully enclosed dry suit, dry hood, full face mask and dry gloves for protection. The dry suit, as you might guess from the name, is designed to keep the diver 100 percent dry with no exposure to contamination.
If at any point a diver in these conditions feels a leak, the dive is immediately stopped. This equipment can all be decontaminated and used again.
The diver can be decontaminated at the waters edge as he exits the hot zone (the water body). In most cases water is suitable to rinse off contamination, but a soap or surfactant may be required to remove residual oil from the equipment.