Which of the following is NOT one of the three types of FDNY permits for flammable gas operations?

The classification of permits for flammable gas operations is crucial for ensuring safety and compliance with regulations. The three main types of FDNY permits in this context include Site-specific, Citywide, and Transportation permits.

Site-specific permits are issued for specific locations where flammable gas operations will take place, ensuring that each site is assessed for its unique risks and safety requirements. Citywide permits are broader and apply to operations conducted across an entire city, allowing for consistent regulatory compliance across multiple sites within urban limits. Transportation permits pertain to the movement of flammable gases, ensuring safety protocols are followed when these materials are transported within city limits.

The option identified is Regional, which does not align with any established permit type specifically designated by the FDNY for flammable gas operations. Therefore, it stands out because it does not fit into the recognized framework of FDNY permits, confirming it as the correct answer to the question. Understanding the roles and definitions of each permit type is essential for anyone engaged in fire guard operations or management of flammable gases.