Health and safety adviser Alan Wright, of Portsoy, Aberdeenshire, struggled to keep his emotions in check as he told how a series of life-and-death decisions secured his freedom from the attack.
The father-of-two – who sent text messages to his wife as he hid in his office – said the reunion with his family was "bittersweet" as the fate of many of his colleagues is still unknown.
There is still no official word on whether Scots Kenneth Whiteside, of Glenrothes, and Barry Lawson, of St Andrews, are alive.
Mr Whiteside's friends and family were dealt a blow on Saturday when one of his colleagues who escaped claimed to have witnessed him being shot. The Algerian co-worker claimed the married father-of-two died "bravely with a smile on his face, despite knowing his fate".
Two days after Wednesday's attack at the In Amenas gas facility, in which six Britons and a British resident are believed to have died, there was still no official word on Mr Whiteside's whereabouts.
His brother Robert, 66, of Crieff, Perthshire, revealed his family are anxiously waiting by the phone. He said: "It is now just a waiting game and we are suffering badly.
"We are trying to keep a lid on our anger at the lack of information, but it is almost more than we can bear at times. The latest report from one of his colleagues has left us devastated."
His wife Stephanie added: "We've had no official confirmation about Kenny. But why would his Algerian co-worker say something like that, knowing the upset that it would cause to his family, if it wasn't true?"
Mr Lawson, a consultant drilling cost controller, also remains unaccounted for.
Meanwhile, Mr Wright described how he managed to escape from the gas plant after he and about 30 other workers became trapped in their office.
The 37-year-old said: "An Algerian employee told us there was a terrorist attack. We had a procedure should something like that happen and we locked ourselves in the office, taped papers over the window so no-one could see inside and sat tight. We sat throughout the day in darkness and silence, sometimes taking the chance to go to the toilet or get some food or drink. Then we decided to move to another room about 6pm.
"We were there until 5am, managing to grab some sleep, while others kept watch."
Throughout the siege he sent regular texts to his wife Karlyn, reassuring her that he was alive.
One text read: "Don't panic. Terrorists in camp. They have accommodation block and factory."
Mr Wright explained that some of the group agreed they were going to try to escape at first light as the wire fence was only 20 yards from their hiding place.
He said: "When I heard the first twang of the wire being cut I was like a rabbit out of the trap. I grabbed a hat and anorak to try and look like a local and made a break for it with the rest of the lads.
"It was like the Great Escape. We all climbed through the fence and ran into the desert as gunfire chattered behind us as the fighting went on."
The escapees ran for about a kilometre until they came across a military post, which proved to be friendly.
Mr Wright was flown to London yesterday morning, where he was reunited with his family, including daughters Imogen, four, and 18-month-old Esme.
He added: "It is a bittersweet reunion for me because I think about those left behind.
"My thoughts are with the other families. I am still waiting to hear what has happened to some of my closest friends."
Scots Mark Grant, from Grangemouth, and Iain Strachan, from Johnstone, are also among 22 British nationals who have managed to escape the siege. Eight Scots are known to have made it out.
A total of 23 hostages have been confirmed dead, with the figure expected to rise.
First Minister Alex Salmond said: "We know two Scots, or people with immediate Scottish family connections, are believed to have been killed. We know eight Scottish survivors are all now back in the UK.
"While eight families can thankfully welcome home their loved ones, our thoughts must be with the families of those who may have been lost in Algeria.
"The Scottish authorities continue to offer every support to all caught up in this crisis, and we remain in close contact with the UK Government.
"We extend our condolences to all those, of all nationalities, who have lost loved ones and colleagues in this terrorist outrage."