Plastic drums are channeling devices which need to be at least ______ inches in diameter and ______ inches tall.

The correct specifications for plastic drums used as channeling devices in work zones indicate that they should be at least 36 inches in diameter and 18 inches tall. These dimensions are important to ensure that the drums are highly visible and effective at directing traffic, particularly in active construction zones or areas requiring diversions.

The larger diameter of 36 inches helps provide a substantial barrier that is noticeable to approaching drivers. This size improves the likelihood that drivers will recognize a change in the road environment, thereby enhancing safety for both workers and motorists. Additionally, the height of 18 inches contributes to visibility without being so tall that it obscures other important traffic control devices or creates an excessive obstruction.

Specific dimensions like these are established in safety regulations and guidelines to provide adequate warning and guidance in potentially hazardous situations, thereby minimizing the risk of accidents in work zones. Understanding these requirements is crucial for anyone involved in traffic control and safety management within construction areas.