Red Seal Plumbing Practice Exam

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Study for the Red Seal Plumbing Exam. Engage with interactive quizzes and multiple-choice questions designed to help you master the essential plumbing concepts. Equip yourself for success on your credentialing exam!

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

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What is the minimum size of water line required for single family dwellings?

15 mm (1/2")
20 mm (3/4")
25 mm (1")
32 mm (1 1/4")

The correct answer is: 20 mm (3/4")

The minimum size of water line required for single family dwellings is typically 20 mm or 3/4". This is because a 20 mm line is able to provide enough water pressure and flow for everyday household uses, such as showering, washing dishes, and doing laundry. Option A, 15 mm, is too small and may result in insufficient water pressure. Option C, 25 mm, is larger than necessary and may result in wasted water. Option D, 32 mm, is also larger than necessary and may be more expensive to install. Overall, 20 mm is the most practical and cost-effective size for a water line in a single family dwelling.