Massachusetts Plumbers Journeyman Practice Exam

Which of the following fixtures are prohibited?

1. Exposed trap urinals

2. Flush valve toilets

3. Urinals with an invisible seal

4. Wall-hung urinals with a visible trap

The correct answer is: Urinals with an invisible seal

The choice indicating that urinals with an invisible seal are prohibited is correct because these fixtures can create issues with hygiene, maintenance, and proper function. An invisible seal can sometimes lead to harboring bacteria and make it difficult to maintain or inspect the plumbing effectively. Therefore, plumbing codes often prohibit such designs to ensure sanitary conditions and ease of access for repairs and cleaning. The other options, while they may present design challenges in some contexts, do not generally fall under prohibitions as strict as for fixtures that cannot maintain hygiene and safety. For example, exposed trap urinals and wall-hung urinals with a visible trap are allowed, provided they meet specific code requirements regarding installation and maintenance. Flush valve toilets are also widely used fixtures that comply with regulations when correctly installed.