Which type of fire extinguisher is best for all types of fires in an elevator machine room?

The ABC extinguisher is the best choice for all types of fires in an elevator machine room because it is designed to extinguish fires involving ordinary combustibles (Class A), flammable liquids (Class B), and electrical equipment (Class C). This versatility makes it suitable for the varied materials and potential hazards present in an elevator machine room, which may include wiring, lubricants, and structural components.

In contrast, a water extinguisher is ineffective for fires involving flammable liquids or electrical equipment, as water can exacerbate these types of fires. A foam extinguisher is primarily effective for Class B fires and can be used on Class A fires, but it is not suited for electrical fires. Similarly, a CO2 extinguisher is effective for electrical fires and flammable liquids, but it does not provide adequate protection against Class A materials, which can be present in such settings. Therefore, the ABC extinguisher's broad-spectrum capabilities make it the ideal choice for addressing the risks associated with fires in elevator machine rooms.