The Scottish Fire and Rescue Service said Martin, from Fife, was in Edinburgh Royal Infirmary with serious injuries. Four other firefighters who were also injured tackling the large-scale fire on Monday have been discharged.
Two were treated for smoke inhalation and two for burns. A police officer was also treated for smoke inhalation in the hospital before being released. The cause of the fire, which triggered a major emergency services response around 11.30am, is still being investigated.
More than 100 firefighters using 22 fire appliances tackled the blaze at the rear of the disused store in Rose Street, with one appliance still on the scene on Tuesday to monitor the building for potential hotspots.
Interim Chief Officer Ross Haggart said: “This was undoubtedly a serious and complex fire. Our thoughts are very much with Barry and his family, and indeed with all of our colleagues who were injured in responding to this incident.
“Barry is a firefighter based in Edinburgh and we ask that everyone please respect his family's privacy at this time. We continue to provide all possible support to our colleagues and their families, as well as all staff involved.
“We are liaising with appropriate partners to ensure a full and thorough investigation is undertaken into this incident.
“Can I please take this opportunity to thank our dedicated crews and staff for their professionalism in responding to this challenging incident; also to our partners for their support on the ground yesterday.
“And of course our thanks go to the health professionals who provided and continue to provide treatment to our injured colleagues and continue to care for Barry.”
A Fire Brigades Union (FBU) spokesperson said: “The thoughts of all of us are with Barry, his family, friends and colleagues and our priority at this time is the welfare of those affected by this incident. FBU officials in Scotland are already addressing this incident and together with FBU head office are making urgent arrangements on the immediate steps required.”
Building owner AAA United, which plans to transform the building into a boutique hotel with retail and food and drink outlets, said initial investigations showed the fire had caused “very localised damage” on the Rose Street side of the building. It has been empty since 2021.
AAA director Anders Krogh said: “We were devastated to find out about the fire shortly after it broke out. Our thoughts and appreciation are with the rescue team.
"Thanks in no small part to great work by workers on site and resolute action from the local fire department.
“The first investigations show very localised damage only in the lower north side of the building. The overall building is intact, but we await further investigations over the following days [to] reveal the total extent of the damage.
“This is a temporary setback for the refurbishment of the Jenners building. Our plan...is first and foremost to help preserve a unique historic building in Edinburgh.
"Hopefully, we will soon be able to reengage on our ambition to bring the Jenners building back to its original glory. But right now our thoughts are only for the well being of everyone involved.”