A winemaker in Italy has died while trying to save his colleague who had passed out in wine vat, according to Italy's fire brigade.

Authorities responded to the emergency call on Thursday at the Ca'di Rajo winery in San Polo di Piave, in the city of Treviso in northern Italy.

According to the fire brigade, the man in his forties was trying to save his colleague who had fainted from carbon monoxide fumes while carrying out maintenance work.

The two men were working in a processing tank that had just been emptied of wine for bottling when they were overcome by fumes from the fermentation process.

Neither men were wearing breathing apparatuses or safety harnesses, according to the fire brigade.

"We are overwhelmed by pain, for us they are two brothers, two sons. My thoughts go to these two men, who grew up with us, and their families," owner of the winery, Simone Cecchetto said in a statement provided to CNN.

"We pray that the young man who was injured recovers as soon as possible," the statement continued, describing the incident as a "huge tragedy."

The General Secretary of local trade union CISL Belluno Treviso is calling for more action to prevent workplace deaths, citing a recent plea by Italian president Sergio Mattarella to beef up training following a spate of workplace accidents including a man who died when cheese rounds fell on him earlier this summer.

"Not even the President of the Republic's appeal to push us to do more for safety, to stop this daily massacre of deaths at work is enough," Massimiliano Paglini said in a statement.