Trane TRG-TRC007-EN manual Answers

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Answers

1Hertz (cycles per second)

2A sound at a single frequency. A sound at a narrow band of frequencies that is significantly greater than the sound at adjacent frequencies would be similar to a tone.

3Sound pressure

4A-weighted sound-pressure level is better for describing outdoor sound

5Noise Criteria rating is better for describing sound in an office or classroom

6NC-35 (see Figure 75)

sound pressure, dB ref 20 mPa

80

70

60

50

40

30

20

10

 

 

 

 

 

 

 

NC-65

 

 

 

 

 

 

 

NC-60

 

 

 

 

 

 

 

NC-55

 

 

 

NC-35

 

 

 

NC-50

 

 

 

 

 

 

 

NC-45

 

 

 

 

 

 

 

NC-40

 

 

 

 

 

 

 

NC-35

 

 

 

 

 

 

 

NC-30

 

 

 

 

 

 

 

NC-25

 

 

 

 

 

 

 

NC-20

 

 

 

 

 

 

 

NC-15

63

125

250

500

1,000

2,000

4,000

8,000

octave-band frequency, Hz

Figure 75

7False

8True

9Receiver sound correction (or room effect)

10Reverberant

11ARI Standard 260–2001,Sound Rating of Ducted Air Moving and Conditioning Equipment

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TRG-TRC007-EN

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Contents Air Conditioning Clinic Fundamentals of Hvac Acoustics Business Reply Mail One of the Fundamental Series Comment CardFundamentals of Hvac Acoustics Fundamentals of Hvac Acoustics PrefaceContents TRG-TRC007-EN Fundamentals of Sound Fundamentals of SoundWhat is Sound? What is Sound?Sound Wave and Frequency Wavelength Broadband Sound and Tones Broadband SoundOctave Bands Octave BandsLogarithmic sums One-Third Octave Bands Sound Power and Sound Pressure Sound Power and Sound PressureAn Analogy Decibel DB = 10 log10 ´ log Logarithmic ScaleEquation for Sound Pressure Equation for Sound Power50 dB + 44 dB = 51 dB Logarithmic Addition of DecibelsHuman Ear Response Sound Perception Rating MethodsHuman Ear Loudness Contours Single-Number Rating Methods Response to TonesSingle-Number Rating Methods Sound Perception and Rating Methods C WeightingWeighting Example Weighting Noise Criteria NC Curves NC-39 Room Criteria RC Curves MPa DB ref Pressure Sound Perception and Rating Methods RC-31 R Phon and Sone Octave-Band Rating Method Octave-Band Rating MethodAcoustical Analysis Acoustical AnalysisSetting a Design Goal Setting a Design GoalAcoustical Analysis Source-Path-Receiver Analysis Acoustical AnalysisSource-Path-Receiver Model Airborne Typical Sound PathsExample of Multiple Sound Paths Examples of a Single Sound PathIdentifying Sound Sources and Paths Sound-Path Modeling Modeling Sound PathsSupply Algorithms for Sound-Path Modeling Computerized Analysis Tools Terms Used in Sound-Path Modeling Attenuation and RegenerationSound Transmission Insertion loss IL Noise reduction NR Transmission loss TL Absorption Reflected Sound Receiver Sound Correction Equipment Sound Rating Equipment Sound RatingFields of Measurement Free FieldDistance Correction in a Free Field = L p1 20 logLot Near Field Reverberant Field Semireverberant Field Hvac Equipment Sound Rating Rating Hvac EquipmentReverberant-Room Method Free-Field Method Industry Standards Ducted Air-Handling Equipment Air Handler Test Configurations Former Methods of Sound Testing ARI Standard Sound Power by Octave Band Review-Period One ReviewNoise criteria NC Room criteria RC Review-Period TwoReview-Period Three Review-Period Four Review Questions for Period QuizOctave-band frequency, Hz Answers Glossary Glossary Room effect See receiver room correction Glossary Trane