The Rion NL-31 is used by many experienced noise professionals who have come to rely upon its rock-solid reliability, ease and speed of use and ease and speed of data handling. Hundreds, if not thousands, of long-term baseline noise surveys have been conducted using the Rion NL-31 with Rion WS-03 Outdoor microphone protection and ANV Measurement Systems weather resistant cases. The system’s reliability, even in harsh weather conditions, and ease of data handling have made it pretty much the industry standard for baseline surveys for windfarms.

• Measures Leq, Lmax, LAmin SEL, up to 5 statistical noise indices (LN) and instantaneous sound pressure levels.
• Stores up to 99,999 sets of data (LAeq, LAmax, 5LNs etc)
• Stores up to 200 hours of 1 second LAeq or 100ms samples
• The word ‘Store’ flashes on the screen once a second when the meter is logging data
• Data stored on to compact flash cards as csv text files which can be read directly by spreadsheet programmes
• Can be used for long-term monitoring with our extremely practical, cost-effective and reliable outdoor kit.
• 100 dB linearity range so you will rarely have to adjust the measurement range
• Pause and back erase function for dealing with extraneous noise
• Sub-channel enabling choice of a second simultaneous time and/or frequency weighting
• Excellent backlit LCD display with numeric and bar graph indication of sound level
• All parameters can be shown simultaneously on one screen, which is really useful for sitework, or each parameter can be shown on separate screens
• Instantaneous sound pressure level can also be viewed in real time on a 20 second level time graph (this can be really useful when using the back erase function)
• The NL-31 is IEC 61672 Class 1 compliant
• The NL-21 is IEC 61672 Class 2 compliant
• Up to 29 hours operation on one set of four alkaline AA cells