Modern micromanometers include a battery to power their electronics, and a display to show the measurement results. Some are equipped with a wireless connection to communicate with a smartphone, computer or tablet app. Most models are also equipped with two measurement inputs to perform differential pressure readings. 

Inspection of air conditioning systems using portable manometers

Ventilation and air conditioning systems must be regularly inspected by HVAC technicians to meet standards and to check that they are working properly. Portable manometers and micromanometers are required for this type of activity.  
 
These types of measuring instruments can be used to assess the clogging of air filters, which ensure good indoor air quality. They will also measure whether there is sufficient air flow in the different supply and exhaust ducts in the various rooms of a building. 

Note that some portable digital pressure gauges are multi-function devices that combine other capabilities to measure different air parameters, such as temperature and humidity. 
 
Note that while the majority of today's portable pressure gauges are digital and based on piezo electric sensor technology, some non-portable pressure gauges are also based on historical liquid column technology. This technology is also very reliable, and has the advantage of not requiring any power supply to operate. These liquid column gauges are therefore excellent safety instruments capable of operating in degraded conditions (power cuts, etc.).