sentences:  Other scientific diving is on projects under the control and direction of the scientists doing the diving, and where this is the case there may be a system with less rigid control as the divers have more responsibility and autonomy.The US works to such a system, where there is an exemption from commercial diving regulation and scientific diving is self-regulated within a national association.The American system has a Diving Control Board taking overall responsibility for all scientific diving work done by an organisation.