Three mineworkers have died at Gold Fields' Kloof mine in the past two days, forcing the company to temporarily shut down the mine.
Two miners died early yesterday and one died on Tuesday in separate rock-fall accidents.
The latest fatalities bring the total number of deaths at the country's mines to 54 since the beginning of the year. More than 70 fatalities were recorded during the same period last year.
National Union of Mineworkers spokesperson Lesiba Seshoka said the union was very disappointed at the company's approach to safety.
"We are very worried that almost all mining houses organised safety talk shops over bottles of beer," he said.
"Gold Fields, in particular, is pursuing public relations exercises calling the media to talk about safety but there is no action."
He also said Gold Fields had a tendency of not reporting fatalities to the public.
Gold Fields chief executive Nick Holland said: "We extend our deepest condolences to the families and friends of our deceased colleagues. These accidents serve to further strengthen our resolve to eliminate all serious and fatal accidents."
Gold Fields is the world's fourth biggest gold producer.