Practice question Diking is used to: Stop liquid flow across a stream by building across the channelBuild a barrier around or in front of a release to contain itChannel runoff into a remote retention areaSuppress vapors with foam Answer: B — Build a barrier around or in front of a release to contain it The correct answer is shown above. Try the full quiz for additional practice. Practice more: Hazmat Operations Practice Questions - NFPA 470 Hazardous Materials Operations Exam →