<h1>Input-output norms ensure imported chemical inputs are matched to export use, requiring verification of proportions.</h1> Standard input-output norms apply to Phosphorous Pentoxide (SION A1142), specifying usable input quantities of White/Yellow Phosphorus per unit and requiring determination of permissible input proportions. Applicants must ensure imported goods correspond to the inputs actually used or required in the declared export product, with imports assessed against those input proportion determinations for compliance.