Swim organizations, for the purposes of their record keeping, often impose other rules. FINA and International Marathon Swimming Hall of Fame do not keep records for swims that employ thermal insulating material, drag reduction fabrics, buoyancy aids, breathing apparatus, propulsion prosthetics, etc. For major channel crossings, most organizations do allow the swimmer to use outside help, an example being that the swimmer swims alongside a boat that uses sophisticated electronics and telecommunications to help the swimmer take the easiest path through surface currents and tides. Such boats can also make the challenge easier for the swimmer by blocking wind and surface chop. Such boats also carry food and hot beverages for the swimmer to consume periodically during the swim (e.g. every 20 to 30 minutes).
In another variant, some swim organizations simply have different sets of records for different equipment scenarios (e.g. wetsuit and non-wetsuit divisions), similar to the structure of free diving record keeping.