The 60-year-old engineer, who would only be known as Garry, said he was working on his vehicle in the yard of Eco Auto Recyclers in the complex, when the fire erupted near the rendering plant up the hill.
As the blaze began burning steadily through vegetation towards the freezing works, Garry kicked into gear, together with Eco owner Chris Robinson, Mr Robinson's employee Kyle Gibson and two others known only as Jamie and Kim.
They cut a hole in a wire fence before wrangling about nine lengths of hose which were connected together and hooked up to the high pressure fire protection system of the old freezing works.
Carrying the heavy 15m lengths of fire hose up the steep hillside towards approaching fire was a ''bit of a haul'' in the baking heat, Garry said.
While he knew what he was doing, having served in the 1980s as a firefighter for the Natural Gas Corporation, he was unprepared for the inferno he met amid the pine trees.
''It was unreal up there, when the pine trees started cracking and fizzing.''
For the next several hours the men battled the blaze, preventing it spreading to the freezing works site.
In that time, tinderbox conditions and flying embers meant the men had to frequently rush to contain spot fires behind the line.
''We caught six or seven jumpers.''
Garry also recounted the relief at being caught under a helicopter's monsoon bucket, which for a time soothed the searing heat.
They were finally stood down when the fire was brought under control about 9pm.
The men did not seek the limelight, and the Otago Daily Times learned of their heroics from Greenwaste owner Bob Gillanders, who lost tens of thousands of dollars worth of plant in the blaze.
''They're the real heroes, '' Mr Gillanders said.
''There's no question in my mind, that fire would have surged through that complex.
''And very few people have thanked them for it.''
