Health authorities in New Caledonia have developped a new pollution warning system for an estimated 40,000 residents near Noumea's SLN nickel smelter.
Once sulphur dioxide and nitrogen dioxide levels reach harmful levels, text messages are being sent to hundreds of key recipients, advising what action to take.
The possible recommendations range from stopping physical exercise to seeking medical care in case of breathing problems.
The new system has been set up with the company Scal-Air amid growing concern over the emissions by the aging nickel plant whose emissions vary depending on the direction of the wind.