In organic coating processes where Class I liquids are exposed to air, fire codes require Class I, Division I electrical installations in hazardous locations to prevent ignition of flammable vapors.
The "immediate vicinity" around pumps or equipment where vapors may accumulate extends 10 feet horizontally from the vapor liberation point in all directions.
Reference to Fire Inspector Documentation:
1. 2021 International Fire Code (IFC) – Section 1503.2.1 (Electrical Installations in Organic Coating Processes)
IFC 1503.2.1 requires that electrical components must be rated for Class I, Division I within 10 feet of vapor sources.
This prevents ignition hazards in locations with flammable vapors.
2. NFPA 33 – Standard for Spray Application Using Flammable or Combustible Materials (2021 Edition) – Section 6.5.2
NFPA 33, Section 6.5.2 states that a 10-foot horizontal zone is considered hazardous and requires Class I, Division I electrical installation.
Detailed Explanation of Answer Choices:
Option A (Incorrect): 5 feet is too short and does not provide sufficient protection from vapor migration.
Option B (Correct): 10 feet is the correct required distance per IFC 1503.2.1 and NFPA 33.
Option C (Incorrect): 20 feet is beyond the required hazardous zone.
Option D (Incorrect): 50 feet is excessive and not required by code.
Thus, the correct and verified answer is: B. 10.
