ICD-10-CM > S00-T88 > T51-T65 > T58 > T58.8 > T58.8X > T58.8X1 T58.8X1 Toxic effect of carbon monoxide from other source, accidental (unintentional) Non-Billable/Non-Specific Codes T58.8X1A..., initial encounterT58.8X1D..., subsequent encounterT58.8X1S..., sequela