noun
flame shielding performance; flame interruption performance; flame screening performance
Technical term used in fire safety and materials engineering to describe a material's ability to block or interrupt flames.
このカーテンは遮炎性に優れている。
This curtain has excellent flame shielding performance.
遮炎性試験の結果を報告する。
Report the results of the flame interruption performance test.
難燃性 means flame retardancy, i.e., the property of being hard to burn, whereas 遮炎性 focuses on shielding or stopping flames from passing through.
Compound of 遮 (sha, 'intercept, block'), 炎 (en, 'flame'), and 性 (sei, 'property, nature').