Oil and petroleum facilities have their own highly effective fire equipment and in these images we see a test being carried out on one of the fire hoses. It is extremely powerful, pumping sea water at high pressure in all directions on a swivel. Of the five (at least) positions that can be seen from my viewpoint, this one is farthest away and is the only one tested on this day.
A close-up of the fire hydrant position closest to me is shown above. The firefighting positions are joined by the grey horizontal gantry shown on the left. Note also that the position has a tall antenna for radio communications across the entire system.