Yes, dial pocket thermometers can be used for both hot and cold temperatures. These thermometers are designed to measure a wide range of temperatures, typically from well below freezing to well above boiling. The dial face usually displays a scale that covers this range, allowing for accurate readings in various environments. 
The thermometer consists of a metal probe connected to a dial, which uses a bimetallic strip or a liquid-filled bulb to measure temperature changes. The bimetallic strip or liquid expands or contracts with temperature changes, causing the dial to move and indicate the temperature. This mechanism is reliable for both hot and cold measurements.
Dial pocket thermometers are commonly used in culinary settings to check the temperature of foods, ensuring they are cooked or stored at safe temperatures. They are also used in laboratories, HVAC systems, and other applications where monitoring temperature is crucial.
However, it is important to ensure that the thermometer is calibrated correctly for accurate readings. Regular calibration checks are recommended, especially if the thermometer is used frequently or in extreme temperature conditions. Additionally, while dial pocket thermometers are versatile, they may not be as precise as digital thermometers, especially for rapid temperature changes.
In summary, dial pocket thermometers are versatile tools suitable for measuring both hot and cold temperatures, provided they are properly calibrated and maintained.