Unlike the fictional Mayfair Ambulance service used in Los Angeles to transport patients to the hospital after being seen by the Squad 51 paramedics, the Shepard Ambulance company was real, and was used under contract by the City of Seattle to transport patients when the four Medic One rigs in Seattle were too busy on calls to be able to transport every patient. The Shepard ambulance shown on the Ferry Klickitat during the explosion was a real ambulance, and visually was better-equipped than the Medic One unit shown in the movie. Shepard was bought by a national ambulance company, AMR, in 1995, but classic Shepard ambulances are still kept in storage at AMR's headquarters and used in parades and for special events. Former Shepard ambulance workers who still work for AMR call themselves the Blue Dogs.
Originally a two-hour Emergency! TV movie, it was split into a two-parter for syndication.
Squad 51 had several boxes in the utility cabinet on the back of their truck: a small black "Old Pal" fishing tackle box containing their medications, and a larger, heavier wood-panel box labeled "IV" containing their IV bags and equipment. But on Seattle Medic One rigs in 1978, they used a large Plano medical-specific tackle box that you see throughout "The Most Deadly Passage" movie, notably in the Kingdome scene, and the M/V Klickitat scene. Seattle's version contains most of the needed drugs in the trays (except for narcotics, which are kept under lock and key in a different box) and all of the IV equipment stored in the bottom, all contained within a single box, which is much more efficient and one less box to carry when reaching patients. Many ALS (paramedic-staffed) public and private ambulances in Washington State still use this same Plano box model to this day, which is still considered efficient. In contrast, L. A.'s version, the "Old Pal" tackle box, is now considered a collector's item and can be worth around $100 on Internet auctions.