Which statement regarding floor drains is true?

The statement that floor drains are not necessary in all animal rooms; but if used, they should be at least 4 inches in diameter is accurate and aligns with industry standards and best practices in animal care facilities.

Floor drains provide a means of removing excess water from animal rooms, which can help with sanitation and minimize standing water that could harbor pathogens. However, they are not universally required in every animal room, as the specific design and requirements may vary based on the use of the room, the types of animals housed, and the overall layout of the facility.

Regarding the size, specifying a minimum diameter of 4 inches for floor drains ensures that they are adequately sized to handle typical flows of water produced during cleaning and maintenance, thus promoting effective drainage and preventing clogging. This requirement addresses practical considerations in flood prevention and sanitation without imposing unnecessary infrastructural constraints on facilities that may not need them.

The other statements imply absolute requirements or specific conditions that may not universally apply across all types of animal facilities. For example, while automatic watering systems may benefit from drainage, it is not an absolute requirement for all installations. Similarly, the requirements for floor drains in animal rooms might differ based on specific circumstances and regulatory guidelines.