After delivery, Irma served on the Bergen–Newcastle route[4] until she was transferred to Norway in the autumn of 1921 to provide voyages for tourists to North Cape and Spitsbergen during the summer season.

The original orders from the military were that the entire battalion was to board Irma for the journey to Finnmark, even though the ship was only certified to carry less than half the number of people involved.

After vigorous protests from both soldiers and officers over safety concerns and overcrowding, the original plan was abandoned and only half the battalion shipped on Irma, the rest leaving some days later on the fellow Hurtigruten steamer Richard With.

[7] The incident with Norwegian conscripts being subjected to attempts to force them to board an overcrowded ship led to a public outcry in Mosjøen.

The Mosjøen newspaper Helgeland Arbeiderblad published an article shortly after the incident criticising the Norwegian military leadership's handling of the troop transport.

[10] Only 25 people survived the sinking of Irma, and for days afterwards dead bodies washed ashore on the Norwegian coast as far north as Namsos.

[11] Before Henry sank she had been able to launch two of her lifeboats and these first saved several of her crew before moving to the location where Irma had gone down and rescuing survivors from floating rafts.

[11] Irma's sinking constituted the last major loss for the Hurtigruten service during the Second World War, with numerous coastal passenger ships having up to that point been lost to mines, air and submarine attacks since the April 1940 German invasion of Norway.

[13] The wreck of Irma was discovered by a geological survey vessel on 3 November 1999 north of Averøya at a depth of 200 metres (660 ft).

A small tugboat which happened to be in the Hustadvika area, the Hopplafjord, which rescued survivors after the sinking of the two ships, being similar to a naval trawler in size and profile, may have been misidentified as an escort vessel by the MTB commander.

[18][19] The day's events concluded with the King leading a ceremony with around 180 invited guests on board the Hurtigruten ship MS Midnatsol over the site of the shipwrecks.