You're troubleshooting a drain backup in an older commercial building. After snaking the accessible cleanouts and finding temporary relief, the blockage quickly returns. The building manager mentions that this issue has been recurring for months. What advanced diagnostic tool would be most beneficial to accurately identify the root cause of the recurring blockage?

Question: You're troubleshooting a drain backup in an older commercial building. After snaking the accessible cleanouts and finding temporary relief, the blockage quickly returns. The building manager mentions that this issue has been recurring for months. What advanced diagnostic tool would be most beneficial to accurately identify the root cause of the recurring blockage?

Answer options:

• A simple plumbing snake with a larger head
• A hand-powered auger ✅ A professional drain inspection camera
• Chemical drain cleaners

Correct answer: A professional drain inspection camera

Explanation: For recurring blockages in older commercial buildings, a professional drain inspection camera is essential to visually identify the root cause, such as roots, collapsed pipes, or significant grease build-up. Snaking provides temporary relief but doesn't show the problem, and other options are less effective for diagnosing recurring issues.