Which of the following are common causes of foam system fouling at a transfer station?

• A. Contaminated concentrate, sediment or debris in lines, incompatible additives, poor filtration, or improper cleaning.
• B. Regular maintenance and thorough cleaning.
• C. Using only distilled water for dilution.
• D. Routine inspection and immediate repair of all leaks.

Answer: (A)

Foam system fouling happens when contaminants and residues build up in the foam delivery path, interfering with concentrate dilution and foam generation. Contaminated concentrate, sediment or debris in lines, incompatible additives, poor filtration, or improper cleaning are classic sources of that buildup because each introduces solids, chemicals that precipitate, or residues that cling to surfaces. This can clog lines, foul injectors, and degrade foam quality, requiring more maintenance and risking system performance. Regular maintenance and thorough cleaning prevent fouling by removing residues and keeping filters and lines clear. Using only distilled water for dilution and routine inspection with prompt leak repairs are preventive practices that reduce risk, not common causes of fouling.