In the event that your business uses or stores extremely hazardous or toxic substances (such as hydrochloric acid or methane), you have to let the community know so that it can prepare itself in the event of accidental spills or emissions of those substances. This is more than just consideration; it is federal law.
The Emergency Planning and Community Right to Know Act is designed, in the event of an emergency, to avoid further catastrophe when unacceptable levels of hazardous materials are released into the environment.
Owners or operators of facilities that have extremely hazardous materials must notify the state's emergency response commission that the facility is subject to the Act.