Which of these statements is true regarding porches in lead safety?

The statement that porches must have a roof and a floor is true in the context of lead safety, as it relates to the structure and design of porches in order to effectively manage lead exposure risks. Roofs and floors are essential components that contribute to the containment and protection from environmental lead hazards. Having a roof can help shield the area from weather-related deterioration that might contribute to lead paint chipping or dust dispersal, while a floor provides a stable surface that can be maintained and cleaned to reduce lead dust accumulation.

In lead safety practices, ensuring that porches are properly maintained with appropriate structural features like roofs and floors helps limit exposure to lead paint that may be present in older buildings. These features also assist in containing any potential lead hazards within the area, effectively managing the risk associated with lead contamination.

The other options do not align with lead safety regulations and best practices. Fully enclosing porches is not a requirement for lead safety measures; it is more about controlling exposure risks. Stating that porches require no specific safety measures undermines the importance of managing lead hazards. Lastly, while detached porches are possible, the focus is more on their condition and maintenance rather than their attachment to the main structure in terms of lead safety.