The power crisis that has struck South Africa can leave citizens and businesses deprived of electricity for hours at a time -- but few victims are more vulnerable than undertakers.

Mortuary directors are urging the bereaved to carry out fast-track funerals to avoid decay and ease pressure on morgue refrigerators.

"The industry is seeing a large number of putrefied bodies," the South African Funeral Practitioners Association (SAFPA) declared bluntly this week.

Burial within four days "is cost-effective and prevents families from seeing their departed ones in a poor state of decomposition," it said.

That could require uncomfortable change in a country where most funerals take place one or two weeks after the death -- and mourners file past an open coffin, with the deceased on view, on the day of the funeral.

Undertakers ease dependence on the state power monopoly Eskom by using diesel generators to keep their morgues cold. But they are being hit with soaring energy bills.

"Smaller parlours are battling to make ends meet because now the majority of their funds are going towards dealing with" the outages, said Dududu Magano, spokesman for the National Funeral Directors' Association.

Scheduled blackouts, known as load shedding, have burdened Africa's most industrialised economy for over a decade, as Eskom's creaking coal-fired plants struggle to meet demand.

But the outages have reached new extremes over the past year, with power sometimes switched off up to four times a day, for periods of up to four and a half hours.

Grace Matila, a Johannesburg undertaker of 10 years, blamed the outages for recently causing her refrigerator's compressor to fail.

"The constant on-and-off caused it to stop working, but luckily I had a back-up compressor. Can you imagine what would have happened if I didn't?" she told AFP, saying she would have to pass on the higher electricity costs to clients.

'Ripple effect'

Industry regulations require funeral parlours and mortuaries to have back-up generators, but not all comply.

"Generators don't come cheap," said Mike Nqakula, who owns a funeral home in the small town of Uitenhage, around 1,000 kilometres (600 miles) south of Johannesburg, adding that many others in his town operate without them.

"I know a guy whose parlour had to shut down because the municipality discovered a decomposed body," the 61-year-old told AFP.

And undertakers' woes don't end with trying to preserve bodies.

The blackouts are also hindering attempts to obtain the administrative documents needed to carry out burials or cremations, since Home Affairs Ministry offices go offline when the power is shut off, said Magano.

The blackouts have caused a "ripple effect" across the sector, he added.

Telephone calls are hit-or-miss when phone batteries are dead and cannot be charged, or network signals are weak because cellphone towers are down.

As a result, people sometimes struggle to contact paramedics so that they can certify a person is dead, or to request body removal when a death occurs at home.