This laboratory realizes, maintains and disseminates the unit of sound, Pascal and the unit of vibration, acceleration (m/s2).
This is conducted with the following standard equipment.
Acoustic measurement
The laboratory has reciprocity calibration equipment as the primary system in acoustic measurement.
The measurement is conducted in pressure field with the use of standard half inch microphones type B&K 4180.
The realisation of the unit of sound pressure, Pascal, by this means traces the acoustical unit to electrical and mechanical quantities.
This set up covers the frequency range from 31.5 Hz to 25 kHz.
The equipment for the set up are signal generator, a band pass filter, reciprocity equipment, voltmeter and a coupler.
The laboratory has acoustic calibrators type 4226 and type 4231
With the two calibrators, the laboratory can calibrate sound level meters (with ¼’’; ½’’ & 1’’ microphones) with a capability from 94 dB, 104 dB and 114 dB at A B & C weightings at 0.2 dB uncertainty within 31.5 Hz to 16 KHz
The laboratory can perform electrical performance for sound level meters by use of the calibration platform type B & K model 3630.
Vibration
In this field, the calibration set-up uses the following equipment;
Shakers, amplifiers, control unit and a PC
The calibration capability in this field is:
Frequency: 5 Hz to 10 KHz
Acceleration: 0 m/s2 to 50 m/s2.
Equipment calibrated includes.
- Sound level meters
- Sound dosimeters
- Accelerometers
- Vibrometers
- Charge amplifiers
Traceability
The laboratory reference standards have traceability to SI.
Contacts:
Head of the laboratory.
Samuel R. Gacheru
E-mail: gacherus@kebs.org
