Canadian armed forces divers Canadian Forces diving is performed by units of the maritime , land , and air environmental commands ( ECs ) , the Experimental Diving and Undersea Group ( EDU Grp ) , and Special Operations Forces ( SOF ) . Divers can be trained as Clearance Diver s ( CL Diver ) , Search and Rescue Technicians ( SAR ) , Port Inspection Divers ( PID ) , Ship ' s Team Divers , and Combat Divers . Clearance divers . Clearance divers use the Canadian Underwater Mine Apparatus ( CUMA ) rebreather breathing apparatus . Canada currently has two operational units from which Navy Clearance Diving Officers , Clearance Divers and Port Inspection Divers perform a variety of core capabilities , as outlined in their Naval Diving Operational Concept of Employment ( ND OCE ) terms of reference . These core capabilities are : They also perform a number of secondary or support functions to these core capabilities include but are not limited to : The two operational naval diving units are : Clearance Divers are considered among the most skilled underwater operators in the world . Their motto is " Strength in depth " . Clearance Diving Officers and Divers also serve at : - Clearance Diving Officers and Clearance Divers also serve at D Dive S ( Director Diving Safety ) at the National Defence Headquarters ( NDHQ ) in Ottawa , Ontario , Canada . Combat divers . History . Diving in the Canadian Army began in the 1960s when , as a result of the introduction of amphibious vehicles , it was essential to provide a diving capability to the safety organization for the swimming of the vehicles . Amphibious operations also required a better capability for the underwater reconnaissance of crossing sites . Following trials in 1966 , diving sections were established in engineer units in 1969 . Once the diving capability was established , additional tasks were added to make combat diving an extension of combat engineering into the water . Other tasks such as obstacle construction and breaching , employing and detecting landmines and limited underwater construction were added to the safety standby and reconnaissance tasks . General Description . Combat divers provide the Army with the capability of performing combat engineer tasks underwater . They generally conduct tasks as part of the combined arms team ; however , if required , they have the ability to execute tasks independently . Combat divers are combat engineers who perform combat diving as a secondary duty . They are grouped into mission - specific teams when a task is identified and ordered , to support operations . Niche area . Combat divers do the majority of their work on inland waterways , either on the surface or beneath the water with breathing apparatus . They usually work close to shorelines and riverbanks because that is where the rest of the army will be conducting operations . At times the combat divers will work in salt water to support Army operations . In some circumstances , combat divers can be used to conduct reconnaissance in the face of enemy forces . They would be doing this reconnaissance with the support of the manoeuvre forces , which could assist the dive team with observation and suppressive fire . Canada ' s Combat Divers are an Occupation Sub - Specialization ( OSS ) in its Army Combat Engineer Regiments . Training . Each of the four dive teams , one located in each of the Canadian army engineer regiments , conducts an intense preliminary selection course ( typically two weeks in length ) to select combat diver candidates for training . Successful candidates then proceed to a Fleet Diving Unit to begin initial dive training , and then proceed to the Army Dive Center at the Combat Training Center to complete the remainder of Combat Diver training . Once this training is completed , combat divers must dive at least once every ninety days in order to maintain their diving currency . Weapons used include : Considering their role in the Army ( demolition , reconnaissance , etc . ) , their weapons tend more towards explosives rather than firearms . As such , each diver typically carries about of high explosives . Such explosives include : The entire line of grenade s , demolition , and pyrotechnics in SNC - TEC , such as Demolition Charge M2A4 , Demolition Charge M3A1 , Trigran Prill s , 40 mm Parachute Rocket Flare C7 , Trip Flare C6 , High Explosive Fragmentation C13 / M67 grenade s . For heavy fire support , the divers ' engineer demolition section uses the C14 Mine Launcher , which can be remotely fired . Considering their job , their land transport is limited , but they have various watercraft . Such craft include :