The Emergency Planning and Community-Right-to-Know Act was prompted by the accident at:

The Emergency Planning and Community-Right-to-Know Act (EPCRA) was indeed prompted by the tragic accident at the Bhopal pesticide plant in India in December 1984, which resulted in a catastrophic release of toxic gas. This incident highlighted the severe consequences of chemical accidents and emphasized the need for better communication and preparedness regarding hazardous substances in communities.

As a direct result of the Bhopal disaster, there was a growing recognition of the necessity for federal laws to ensure that local governments and communities were informed about hazardous chemicals present in their areas. EPCRA was enacted in 1986 as part of the Superfund Amendments and Reauthorization Act (SARA) to promote emergency preparedness and public awareness, involving the reporting of hazardous chemicals by various industries and providing the public with access to information regarding these substances.

The other events mentioned—Three Mile Island, and Chernobyl—were significant nuclear accidents that certainly raised awareness about safety and emergency preparedness in different contexts, while sulfur dioxide does not correspond to a specific incident in the same way. However, it was the Bhopal disaster that specifically led to the creation of EPCRA, focusing on chemical hazards in a community context.