Fires involving combustible metals with fuels such as sodium, potassium, or magnesium are Class D fires. Which agent is commonly used to control these fires?

Fires involving combustible metals with fuels such as sodium, potassium, or magnesium are Class D fires. Which agent is commonly used to control these fires?

• A. WATER
• B. FOAM
• C. DRY CHEMICAL
• D. SAND

Answer: (D)

Fires involving burning metals need to be starved of oxygen and cooled so the metal won’t reignite. The simplest, most practical way to achieve that on a boat is to blanket the flame with a non-reactive, heat-absorbing material. Sand does this well: it covers the burning metal, cuts off the air supply, and absorbs heat, helping to smother and cool the fire. It’s readily available on ships and safe to use with common metal fuels like magnesium, sodium, or potassium. Water would react violently with these metals and can produce dangerous hydrogen gas, foam won’t effectively smother a metal fire, and while there are specialized metal-fire powders, sand is the most practical, widely used option in many marine situations.

Fires involving burning metals need to be starved of oxygen and cooled so the metal won’t reignite. The simplest, most practical way to achieve that on a boat is to blanket the flame with a non-reactive, heat-absorbing material. Sand does this well: it covers the burning metal, cuts off the air supply, and absorbs heat, helping to smother and cool the fire. It’s readily available on ships and safe to use with common metal fuels like magnesium, sodium, or potassium. Water would react violently with these metals and can produce dangerous hydrogen gas, foam won’t effectively smother a metal fire, and while there are specialized metal-fire powders, sand is the most practical, widely used option in many marine situations.