Phosphorus by ICP

Processing Specification:

Phosphorus content must be kept as low as possible because of its detrimental effect on catalytic converters. Phosphorus coats the catalyst in the converter and renders it ineffective in treating the exhaust. Phosphorus content is measured by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) in accordance with ASTM D4951.
ASTM D6751 Requirement: a maximum phosphorus content of 0.001% mass (10mg/kg).