Ignition-quenching covers are configured to quench an ignition event in a combustible environment triggered by an ignition source associated with an ignition-risk structure. Ignition-quenching covers comprise a porous body that includes two or more porous elements and are configured to cover the ignition-risk structure, wherein the ignition-risk structure is associated with a potential ignition source that may produce the ignition event in the combustible environment. The porous body defines passages sized to quench the ignition event. Methods comprise installing a porous ignition-quenching cover over an ignition-risk structure to prevent bulk combustion, e.g., of a fuel vapor in a fuel tank, due to an ignition event associated with the ignition-risk structure.