What is the name of the clause in insurance policies that excludes coverage for losses due to radioactive contamination?

The clause that excludes insurance coverage for losses caused by radioactive contamination is the nuclear exclusion clause.

It is commonly found in property and liability policies, where wording may exclude loss arising from nuclear reaction, radiation, or radioactive contamination, whether the cause is direct or indirect. The exclusion reflects the potentially catastrophic scale of nuclear accidents and the specialized insurance and government frameworks created to address them.

Nuclear exclusions became especially important as civilian nuclear power expanded after World War II. In the United States, the Price–Anderson Act of 1957 established a system combining private insurance with federal indemnity for nuclear incidents. That arrangement helped make nuclear liability insurable while keeping ordinary home, business, and general-liability policies from absorbing unlimited nuclear risk.

A common mix-up is confusing this clause with pollution or terrorism exclusions. Those may restrict other categories of loss, but radioactive contamination is specifically identified by the nuclear exclusion. Coverage can also vary by policy type: nuclear exclusions are associated mainly with property and liability insurance, not every form of insurance.