Measurement of Sound Source Noise:

Principles for noise source monitoring point placement:

Avoid large reflective surfaces near the sound source; if the sound source is indoors, the measurement point should be set outdoors; the measurement point should be on the side facing the factory boundary.

2. Original Records

Operating conditions; type of sound source and machine model number; mark the position of the sound source on the illustration of measurement points, and each noise source mentioned in the report corresponds to one on the illustration.

No background value testing required.

3. Condition Monitoring

Heat Pump Units: Each heat pump unit typically consists of 2-3 heads, each being an independent noise source. Please specify the number of operating heads and the unit serial number when recording.

Features both cooling and heating settings, automatically activates once the set temperature is reached.

Pump House: Available in underground and above-ground types. Pump houses typically come with water tanks, and pumps are categorized into overhead pumps and variable frequency pumps.

For untreated pump rooms, the operational supervision should focus on whether the variable-speed pumps have reached the specified load. For treated pump rooms, the operational supervision should be on whether the incoming water pipe of the water tank is receiving water.

Other common noise sources include: outdoor units of air conditioners, air compressor rooms, refrigeration rooms, fresh air exhaust fans, and exhaust hoods for kitchen fumes, etc.

Other special noise sources, such as audio equipment and large power generation sets, are to be monitored in accordance with the respective standard testing methods.