Where should an equipment shutoff valve be installed for nonmetallic gas hose connectors in indoor use?

The requirement for an equipment shutoff valve to be installed near the appliance for nonmetallic gas hose connectors in indoor use is critical for safety and accessibility. This positioning allows for immediate access to the valve, enabling users to quickly shut off the gas supply in case of an emergency or a system malfunction. By installing the valve at this location, it reduces the risk of gas leaks and enhances the overall safety of the installation. Additionally, having the shutoff valve close to the appliance ensures it's readily available for service or maintenance purposes without needing to navigate through the building to reach other shutoff points, which could be further away and less accessible.

The other choices present alternatives that are less practical or not in line with safety guidelines. For example, placing the valve at the building entrance would not provide the necessary immediate access to turn off the gas supply for specific appliances. Similarly, attaching it to the building piping or placing it at the gas meter could complicate access and response time, which is not ideal during urgent situations. Therefore, the most logical and safe location for the equipment shutoff valve is directly near the appliance it serves.