ICC Commercial Mechanical Practice Exam

The maximum spacing allowed for cleanouts located on horizontal sections of grease ducts in commercial kitchen ventilation systems is 20 feet. This requirement is in place to ensure that the ducts can be properly maintained and cleaned, which is critical for fire safety and the effective removal of grease and other residues that can build up over time.

Grease accumulation within ducts poses a significant fire hazard, making it essential for these systems to have accessible cleanouts at regular intervals. By setting the limit at 20 feet, the code provides a balance between allowing for efficient duct design and ensuring that the necessary maintenance can be performed without excessive difficulty. Adequate spacing ensures that cleaning crews have sufficient access to remove blockages and perform inspections, which contributes to the overall safety and maintenance of the kitchen ventilation system.