 Historically, scuba diving was considered a relatively high risk activity, but this perception has been modified by the developments in equipment, training and service provision.Medical support services and local availability of decompression chambers and on-board medical oxygen for first aid has increased, improving the management of diving accidents and reducing the risk of permanent injury.The dive tourism industry tends to provide rental equipment to travelling divers more than equipment sales and service, but those aspects are considered valuable adjuncts.