Am I required to update the information in the written report?

Yes. You must use DOT Form F 5800.1 and check the “A supplemental (follow-up) report” box on question #2 to provide additional information after the initial report. You are required to provide updates for up to one year after the initial filing if more information is gained or new developments arise concerning the following, for example:

• A death results from injuries caused by a hazardous material;
• The person responsible for preparing the original report learns that there is a misidentification of hazardous material or package information;
• Damage or loss or related costs that were not known at the time the report was filed become known; or
• Revised estimates of damages, losses, and related costs result in a change of $25,000 or more, or 10% of the original cost estimates, whichever is greater, even if the original estimate was under $500.