Which item is NOT listed as a visual indicator of chemical actions?

• A. Vapor cloud
• B. Ice-cold air temperature
• C. Dying or discolored vegetation
• D. Containers bulging

Answer: (C)

Visual indicators of chemical actions are signs that a release is actively occurring and that immediate protective actions may be needed. A visible vapor cloud clearly shows a chemical is present in the air. Ice-cold air around the scene can occur with certain releases and helps signal a rapid energy exchange and exposure risk. Containers bulging indicate internal pressure from a gas buildup, pointing to a leak or reaction inside the container. Dying or discolored vegetation, while it can be related to spills, is not a rapid, reliable visual cue used to identify an active chemical action at the site. It’s more of a downstream environmental effect than an immediate scene indicator.