According to NFPA standards, what is the type of fire pump you generally cannot use?

The type of fire pump that is generally not utilized according to NFPA standards is a gas engine. This is primarily due to safety concerns and performance reliability in emergency situations. Gas engines may pose a higher risk of failure or operational issues when compared to diesel or electric engines, especially under the high-demand scenarios often required in firefighting situations.

Both diesel and electric engines are widely accepted for fire pumps as they provide reliable and consistent power. Diesel engines are especially favored because they tend to be more robust and can perform better in adverse conditions. Electric engines are also a common choice due to their efficiency and ease of maintenance. Natural gas engines, while sometimes seen in other applications, are not typically employed for fire pumps because of similar reliability concerns and the fact that their power may not be as dependable during an emergency where a fire is present.

Thus, considering the operational requirements and reliability of fire pumps, gas engines are generally not considered suitable for use in fire protection systems as per NFPA standards.