[en] The performance of an apparatus for measuring continuously the sulfur content of coal entering a 3000-MW electric generating power station is described. The apparatus, known as a Sulfurmeter, interrogates a sidestream of coal in a nondestructive fashion using prompt neutron activation analysis (PNAA). Preceding the Sulfurmeter is a coal-handling facility that blends a 1% S coal with a 3% S coal. The Sulfurmeter is used to evaluate the blend, which must meet an emission standard of 3.68 lb of SO₂/10⁶ Btu when fired. Sulfur measurements by the PNAA apparatus were compared with those from traditional ASTM chemistry - satisfactory agreement was obtained