What must be ensured about the heating and cooling systems during an event?

Ensuring that heating and cooling systems do not obstruct exits or pathways is critical for safety during an event. This is because clear access to exits is a fundamental requirement in any indoor assembly area, as it directly impacts the safe egress of attendees in the event of an emergency. Any obstructions could pose a serious risk, potentially hindering the swift evacuation of individuals, which is essential for their safety.

While maintaining a comfortable temperature and low maintenance are important factors to consider for overall comfort and operational efficiency, they do not directly relate to safety concerns in the same way that clear pathways do. Similarly, enhancing audio-visual experiences, while beneficial for attendee engagement, is not related to the critical safety standards that govern the placement and functionality of heating and cooling systems. Hence, ensuring that these systems do not block exits or pathways is paramount in the context of safety at an indoor assembly.