Validation and qualification of an HVAC system comprises integration of various technologies together. Anemometer, particle counter, LLM, SLM, filter integrity are some of the technologies that are combined together to develop an accurate result for validation. 
Tests that are performed during validation are:
1. Air Velocity Test
2. Lux Level Test
3. Particle Count
4. Sound Level Test
5. Filter Integrity Test
6.  Air Flow Test
7. Temp. RH measurement
Air Velocity Test
A device used to measure the velocity of air flow is used in this test. Air balancing in supply grills and AHU is done by using this device called anemometer. The vane anemometer must have its axis parallel to the direction of the wind and therefore horizontal. Certain protocols are followed while using this device over supply and return grills.
Lux Level Test
Lux is the SI derived unit of illuminance. Illuminance is a measure of how much luminous flux is spread over a given area. We can understand the luminous flux as a measure of the total amount of visible light present in that area. LLM is used to measure the lux level in a specific area.
Particle Count Test
Viable & non-viable particle particles present in air are removed by the use of filters, but the presence of these particles inside a space is measured by using a device called a particle counter. Various types of particle counters are available in industry like optical, aerosol, liquid, solid, etc. The test verifies the proper functioning of the HVAC system whether it is working as per the design.
Sound Level Test
HVAC systems could be a noisy system if parameters are not precisely controlled. SLM is an acoustic measurement hand held device used to measure the noise level of HVAC systems. Two classes of SLM exist with different tolerance of error, used according to level of tolerance in that industry.
Filter Integrity Test
Manufacturers are obligated to test the filter for integrity before and after the production cycle. By performing a filter integrity test it’s proved that the filter is fully functional and that no unwanted components are passing through it. In practice, there are destructive and non-destructive tests, both being used according to the nature of clean room purpose.
Air Flow Test
Visualizing the flow of air to understand the flow path when air leaves the supply grill is carried out by using the portable visible vapour generator and taking a video graph. The main purpose of airflow visualization test is to show the actual airflow pattern throughout the clean room is unidirectional. The test may also be used to demonstrate the effects on airflow caused by equipment.
Temperature RH Measurement
Suitable temperature and humidity is a prominent output of any HVAC system, and to give accurate results, regular check-ups are required. A Digital Hygrometer is used to measure the temperature and humidity of a clean room.