In general, hyperbaric chambers are an essential part of the sport of scuba diving. Since they both have to breathe gases while being subjected to pressures higher than atmospheric, patients treated in hyperbaric chambers are physiologically comparable to scuba divers. Patients undergoing HBO 2 treatment, on the other hand, stay dry during the procedure and breathe oxygen at a concentration of one hundred percent, in contrast to divers who are completely submerged in water.