* Mining deaths fell for 8 years running but now rising
* Netting credited with saving lives in deep South Africa mines
* Government stepping up production halts for safety
* Industry says such stoppages often misplaced, cost output
* GRAPHIC - Mining safety: tmsnrt.rs/2bFgd8k
By Ed Stoddard and Sisipho Skweyiya
PHUTHADITJHABA, South Africa, Aug 31 (Reuters) - Pakiso Matsemela recalls the day he lost the use of his legs, joining the long casualty list of a South African mining industry whose accident rate is again climbing after years of improvement.
"I heard a bang and suddenly I was hit in the back by a rock. It felt like a rush of heat," the 63-year-old told Reuters, recounting the accident that shattered his spine at the Northam Platinum mine.
That was in May, 2009 and - while of no consolation to the paralysed Matsemela - South Africa's mines were at the time gradually getting to grips with their appalling safety record.
With an unforgiving geology, South Africa is home to the world's deepest mines where workers labour up to 4 km (2-1/2 miles) beneath the surface. Nevertheless, the industry had been making great safety strides, with mining deaths falling for eight straight years - until this year.
The stakes are high with the mining firms, which are major employers in an economy with a 25 percent jobless rate, under pressure from the government and investors alike to improve safety. So too are the political stakes in a country still haunted by apartheid, when critics say profits counted for more than the lives of black miners.
Today those profits can be marginal. Platinum prices, for example, are still languishing after a global commodities downturn despite a modest recovery this year, while improved safety measures - as well as production stoppages due to accidents - come at a cost.
Boardrooms are wary: global mining group BHP, which has spun off its South African operations, says it will not invest in platinum because of the risks.
"We think every one of our fatalities is avoidable. Platinum cannot be managed safely. Platinum is in very deep mines, with very narrow seams, which are geologically unstable," said BHP spokesman Ruban Yogarajah.
One simple innovation has started saving scores of lives: netting to catch falling rocks at the face, or stope, where drilling and blasting take place.
The government has stepped up safety inspections - but the industry says sometimes inspectors have imposed arbitrary work stoppages over safety, costing billions of rand in lost output and putting mines and jobs on the line.
The mines ministry says the upturn in the death toll shows the need for the stoppages, and has signalled it will increase scrutiny. In July it hired 38 more inspectors.
Back in 1993, the year before Nelson Mandela became South Africa's first black president, 615 miners died in the pits. By 2009 - when Matsemela suffered his accident - the rate had dropped to 167 and it kept falling, reaching 77 in 2015, the Chamber of Mines said.
But so far this year, the death toll has risen to 59 from 48 in the same period of 2015. This has been attributed to a series of lay-offs which unions say have perhaps driven workers, fearful for their jobs, to take risks to lift production.
"That increases the pressure on the workers. So there is an increased focus on production and that causes increased risks," said Paul Mardon, head of the safety department at the union Solidarity.
Neal Froneman, chief executive of gold and platinum producer Sibanye Resources, told Reuters: "There could be production pressure that results in people putting production ahead of safety - not that we condone that."
South Africa's fatality frequency rate - a ratio of deaths per million hours worked - fell to 0.08 in 2015 from 0.3 in 2003. That remains higher than other mining jurisdictions such as Australia but the gap is narrowing.
The drop in deaths picked up pace in 2010, when fatalities fell 24 percent to 127. This was when South African producers embraced the use of safety nets at the stope.
Froneman said falls of ground or rocks tumbling from above were a predominant cause of fatal accidents.
"If there are minor falls of ground there is a net that catches it. That is a huge initiative and in fact has cost a lot of money but there is no problem with that," he said.
At the depths mined in South Africa, falls of ground are almost inevitable. Hence the focus on minimising the consequences of such incidents, which often take place at the stope, where a miner with a drill bores holes for explosives.
Results are encouraging. In 2003, falls of ground accounted for 131 of 267 deaths in South Africa's mines. In 2015, they caused 22 out of 77.
"Safety nets have proven their worth. Nets have caught rocks that would have almost certainly have killed," said August Lamos, a mining engineer at the University of the Witwatersrand.
But nets can only do so much. Seismic events can unleash rubble that would overwhelm any net.
The government and industry target is "zero harm" but Lamos said technology has limits. "You won't ever get a year in South African mining without fatalities."
Mechanisation - replacing humans with machines - has been introduced at some mines. But most gold and platinum seams are too narrow and steep for machines to access.
And technology cannot remove human error. This is where some of the friction with inspectors is emerging.
Sources at Sibanye say the firm's Kroondal Platinum mine was shut for two days after a vehicle driver failed to brake, injuring himself.
Executives say that while work stoppages are often justified, this kind of blanket halt is not. When a mine is shut, output is lost while idle miners get paid.
A Reuters poll of South African mining companies found seven reported increases in stoppages in the first seven months of this year while four had decreases. One company with a decrease still had over 100 stoppages in the first seven months of 2015.
Tallies from half a dozen producers show lost production from safety stoppages in 2016 so far have cost 2 billion rand ($138 million), and this is far from the industry total.
Producers, mindful of safety, say they impose their own stoppages. In 2014, Gold Fields' CEO Nick Holland shut most of the South Deep mine for three months because he was not happy with its support systems.
"We lost a huge amount of market value but sometimes you have to take hard decisions on safety," Holland told Reuters.
But in Phuthaditjhaba, a sprawling mountain township where Matsemela now lives, the paralysed ex-miner feels cheated. "I contributed so much to the economy of this country. And now I lead a life like this," he said.
($1 = 14.4650 rand)
Additional reporting by Barbara Lewis in London and Dinky Mkhize in Phuthaditjhaba; Editing by James Macharia and David Stamp