The Optimus Red has been specifically built to carry out occupational noise measurements. All Optimus Red variants meet the Noise At Work Regulations. The C & D variants of the Optimus Red also feature real-time octave band filters, which will measure the noise in 10 different frequency bands. The D variant adds NR & NC values and curves to the 1:1 octave band measurements. This information an be useful in checking the performance of HVAC Systems and noise level in rooms. A Bluetooth connection allows you to pair your sound level meter with your Android or iOS mobile device, enabling you to control your instrument remotely. With this feature you can also see a live feed of the data being recorded and download the overall measurement values.