Manometers

Select based on the pressure range, required accuracy, and medium (air, noncorrosive gases, or liquids). For low differential pressures and HVAC work, choose a low-range digital manometer; for higher pressures or process work, choose a gauge or compound manometer with an appropriate maximum pressure rating and accuracy class

Choose accuracy based on how precise your measurements must be; common handheld digital manometers offer ±0.5% to ±1.5% full-scale accuracy. Resolution (displayed units) is useful for small changes—look for at least 0.01 units for fine measurements and confirm the device's stated accuracy rather than relying on resolution alone

Ensure the manometer supports the pressure units you need (Pa, inH2O, psi, bar, mbar) and look for features like data hold, min/max, zeroing, unit conversion, and a backlit display. Additional useful features include differential measurement, built-in pumps for some HVAC tasks, data logging, and durable probe/port fittings

For industrial environments, choose models with robust housings, impact resistance, rubber bumpers, and ingress protection ratings (IP54 or higher) to resist dust and splashes. Also check that ports and hoses use durable fittings (metal or reinforced polymer) compatible with your test connections

Store in a clean, dry place and protect ports and tubing from contamination. Perform periodic calibration per manufacturer recommendations or industry standards—typically annually for routine use—and check zero offset before critical measurements

Not always—confirm compatibility with the manufacturer: many handheld manometers are intended for air and noncorrosive gases, while liquid measurement may require specific seals, fittings, or a liquid-filled manometer design to avoid damage or inaccurate readings