US environmental regulators tighten sulfur dioxide limits, but only for some pollutants

The US Environmental Protection Agency is changing how it measures sulfur dioxide in the air. It will now use an annual average over three years, with a lower limit of 10 parts per billion. This means industries that release sulfur dioxide will face stricter, more consistent monitoring.

For decades, air quality standards have been a balancing act between public health and industrial costs. This change means that facilities emitting sulfur dioxide will need to invest in better pollution controls or face penalties. It also means that communities near these facilities should see cleaner air, as the new standard aims to prevent long-term ecological damage.