Final answer:
In the context of reportable quantities of substances, such as hazardous materials or adverse drug events, reporting times can vary. For adverse drug event reporting to the FDA, serious and unexpected events must be reported within 15 days, with others reported quarterly.
Step-by-step explanation:
When a spill occurs of a Reportable Quantity (RQ) substance, the carrier must report the spill immediately, but there is no specific time frame mentioned in the question. As per guidance from regulatory agencies like the United States Environmental Protection Agency (EPA) for hazardous substances, or in the context of drug-related incidents, the Food and Drug Administration (FDA) has set reporting requirements. Reporting serious and unexpected adverse drug events must be done within 15 days, while other events are to be reported on a quarterly basis. In the case of adverse drug events, sponsors review and report to the FDA following New Drug Application (NDA) approval, including reports received through the MedWatch program.