Inside California's porn industry

California produces some 85 per cent of the world's commercial pornographic movies with revenues that run into billions of dollars.

But the industry has hit challenging times caused by the global downturn, and by piracy.

DVD sales have collapsed, some companies have gone bust and now a new get-tough approach is putting pressure on the industry to conform to basic health and safety standards.

The BBC's Ed Butler visits film sets and talks to porn stars and industry insiders, about the challenges ahead.

For copyright reasons the audio of this program is not available for download.