Volunteer firefighters, many from Indigenous Dayak and Banjar communities, are battling relentless wildfires across Indonesian Borneo that have burned around 200,000 hectares of forest and farmland since early July. The fires are especially alarming because they are tearing through vast tropical peatlands, ancient carbon stores that can release huge quantities of carbon dioxide, carbon monoxide and methane when they burn, earning them the nickname "carbon bombs". Amid a "Super El Niño" driving severe drought, the resulting haze has spread across national borders, creating one of the region's worst pollution crises in over a decade.

Kalimantan's peat deposits can exceed 20 metres in depth, with a hectare of the deepest peat holding more than 6,000 tonnes of carbon, roughly equivalent to the annual emissions of 4,800 cars, which experts warn can be released rapidly once fires take hold. The haze has spread to Singapore, Manila and Kuala Lumpur, pushing air pollution indices to "unhealthy" levels described as nearly 75 times WHO recommended limits in places, and triggering a surge in hospital admissions. Indonesia's Health Ministry recorded over 50,000 respiratory infection cases linked to the fires between July and August, more than 12,000 of them in children under five, while volunteer firefighters like 35-year-old Fahrin Ramadhianto continue battling the blazes using hand tools, carts and portable pumps.