California cement kilns must now meet tighter nitrogen oxide limits

US environmental regulators have approved a new rule for cement kilns in California's Eastern Kern Air Pollution Control District. These kilns must now reduce their emissions of nitrogen oxides, which contribute to smog and air pollution.

This change means cement manufacturers in this part of California will need to upgrade their equipment or change their processes to meet the new, stricter pollution standards. It makes it harder for them to operate without investing in cleaner technology. This is a small but concrete step in the ongoing effort to reduce industrial air pollution in California.