The picture accompanying this cloudcast depicts a deadly cloud of hydrofluoric acid gas released at a chemical plant in South Korea back in 2012; it killed five and severely injured 18, and thousands who lived near the plant fled in terror - and for good reason. If accidentally splashed on the skin, the damage caused by hydrofluoric acid may be at first unnoticeable, but will soon become unbearable. It is subtle, insidious, and brutal in its destruction of the human body - a real-world horror worth keeping in mind while celebrating Halloween.
