Which type of fittings is strictly disallowed in the Halon 1301 system?

In the context of a Halon 1301 system, the use of fittings is crucial for the effective and safe operation of the fire suppression system. The choice that specifies Class 150 lb fittings as being strictly disallowed aligns with the requirements and standards for components used in Halon systems.

Class 150 lb fittings are rated for lower pressure applications and may not be suitable for the higher pressure conditions often found in Halon systems. These systems require fittings that can withstand the specific pressure and temperature ranges associated with the discharge of Halon 1301, and failure to use appropriate fittings could lead to system inefficiencies or potential hazards during operation.

While brass, plastic, and steel fittings might have varied degrees of suitability, it is the Class 150 lb fittings that do not meet the necessary pressure rating and are, therefore, prohibited. Ensuring the proper type of fittings are used is fundamental to maintaining the integrity of the fire suppression system and ensuring optimal performance in an emergency situation.