What must outdoor regulators be protected from?

Outdoor regulators must be protected from sleet, snow, or debris because these elements can interfere with the proper functioning of the regulator. The presence of ice or snow may obstruct airflow or cause physical damage to the regulator, potentially leading to operational issues or safety hazards. Additionally, debris can get lodged in the device, which can affect its performance and safety.

While it's important to consider the other environmental factors mentioned, safeguarding regulators specifically from sleet, snow, and debris is crucial for maintaining their reliability and ensuring that they operate correctly in outdoor conditions. This protection helps prevent malfunction due to the accumulation of damaging materials or hindered operation from freezing conditions.