ICD-10-CM > S00-T88 > T36-T50 > T48 > T48.9 > T48.99 > T48.994 T48.994 Poisoning by other agents primarily acting on the respiratory system, undetermined Non-Billable/Non-Specific Codes T48.994A..., initial encounterT48.994D..., subsequent encounterT48.994S..., sequela