Section Cover Page
Section 275119
2010-11-15Self-Contained Sound Masking System

Use this Section to specify an electronic sound masking system comprised of selfcontained units strategically located above suspended acoustic tile ceilings. Each selfcontained master unit generates a unique, diffuse, and unobtrusive sound with a spectrum shape designed to mask speech and unwanted noise.

This Master Specification Section contains:

.1This Cover Page

.2Specification Section Text:

1.General

1.1Related Requirements

1.2Product Options and Substitutions

1.3Reference Documents

1.4System Description

1.5Performance Requirements

1.6Submittals

1.7Installer Qualifications

1.8Performance Verification by Minister

1.9Scheduling

2.Products

2.1Proprietary Products

2.2Components

3.Execution

3.1Installation

3.2Testing, Adjusting, and Balancing

3.3Schedule

BMS Basic Master Specification
Alberta Infrastructure
Master Specification System / Page 01
Section 275119
Plan No:Self-Contained Sound Masking System
Project ID:Page 1

1.General

1.1RELATED Requirements

SPECNOTE: This Section does not include requirements for electrical wiring. Specify appropriate cross references, dependent on whether the BMS (basic) or SFMS (short form) electrical master specification is being used, respectively.

.1Electrical General Requirements:Section 260010.

.2Wire and Cable:Section 260513.

.3Electrical Starting and Testing General Requirements:Section 260810.

OR

.1Basic Electrical Requirements:Section 260005.

.2Basic Electrical Materials and Methods:Section 260501.

.3Electrical Starting and Testing General Requirements:Section 260810.

1.2PRODUCT OPTIONS AND SUBSTITUTIONS

.1Refer to Division 01 for requirements pertaining to Product Options and Substitutions.

1.3reference Documents

.1American National Standards Institute (ANSI):

.1 / ANSI S1.4-1983(R2006) / Sound Level Meters
.2 / ANSI S1.11-1986(R2009) / Octave-Band and Fractional Octave-Band Analog and Digital Filters

1.4DESCRIPTION OF SYSTEM

.1Provide an electronic sound masking system installed above suspended acoustic tile ceiling in areas indicated.

.2System shall be comprised of strategically located selfcontained units which generate a unique, diffuse, and unobtrusive sound with a spectrum shape designed to mask speech and unwanted noise.

.3System shall be comprised of [master units only] [master and satellite units, with each master unit driving a maximum of [one] [two] satellite units].

1.5PERFORMANCE REQUIREMENTS

.1Provide, in areas indicated to receive sound masking, as many units as are necessary to meet specified acoustical performance requirements.

.2Octave Band Sound Pressure Levels:

Octave Band Centre
Frequency(Hz) / Average Sound
Pressure Level(dB) / Tolerances(dB)
125 / [46] [] / +33
250 / [43] [] / +22
500 / [39] [] / +11
1000 / [35] [] / +11
2000 / [30] [] / +11
4000 / [24] [] / +11
8000 / [16] [] / +22

.3Spatial Average Overall Sound Pressure Level:Minimum [40] []dB and maximum [42] [] dB, Aweighted.

1.6SUBMITTALS

.1Comply with requirements of Section [260005] [260010].

.2Submit shop drawings indicating proposed quantity and location of all system components and related wiring and accessories.

.3Obtain Minister's approval for any changes in quantity or location of sound masking units from Minister reviewed shop drawings.

.4After completing installation, testing, adjusting and balancing, submit the following:

.1Project record drawings in the form of the above noted shop drawings, revised as necessary to accurately indicate locations of all system components, as installed.

.2Copy of all final sound pressure level readings taken, including accurate description of reading locations and test methods and equipment used.

1.7INSTALLER QUALIFICATIONS

.1 System components shall be installed by a qualified installer approved by component manufacturer. Work shall be done by technicians with experience installing and adjusting self-contained sound masking systems.

1.8PERFORMANCE VERIFICATION BY MINISTER

.1Minister will appoint and pay for services of testing agency or utilize his own forces to take measurements to verify that the installed sound masking system meets specified acoustical performance requirements.

.2Performance verification will be performed [After Interim Acceptance of the Work] [During Performance Testing, and sub-phases of Facility Start-Up].

SPECNOTE: Unless Facility Start-Up program is being employed on project, specify time of performance verification as after Interim Acceptance.

1.9SCHEDULING

SPECNOTE: If requirements in this article are not practicable, revise as necessary.

.1Scheduled installation, testing, tuning, and balancing to be performed after normal working hours of facility users, or as otherwise required by Minister.

SPECNOTE: Specify installation, etc. after normal working hours, in an occupied facility.

.2Scheduled testing, adjusting, and balancing to be performed after aboveceiling mechanical and electrical work, suspended acoustic tile ceiling, and sound masking system installations are all complete.

2.Products

2.1PROPRIETARY PRODUCTS

.1Provide sound-masking units manufactured by one of the following manufacturers, at Contractor’s option:

.1AccuMask Models PLM and PLS, manufactured by K.R.Moeller Associates Ltd., Oakville, ON, and distributed by Sound-Rite Acoustics Inc., who may be contacted as follows:

.1For projects located within area code 780, the Edmonton representative: tel:(780)414 1756; fax: (780) 414 6553.

.2For projects located within area code 403, the Calgary representative: tel:(403)2960505; fax: (403)2960511.

.2Spectra Plenum Series Models LM6 and LS6, manufactured by Lencore Acoustics Corp., and distributed by PCC Group Inc., Calgary, tel. (403) 267-2405; fax (403) 267-2404.

2.2COMPONENTS

.1Master Units:Comprised of the following components:

.1Digital random noise generator.

.2Solid-State power amplifier with output gain adjustment.

.3Adjustable lowpass filter or octave band equalizer.

.4Wireless infrared control or enclosure-mounted potentiometer control of the level and contour adjustments.

.5Full-range, wide-dispersion loudspeaker.

.6Metal enclosure and mounting hardware.

.7Electrical connections.

.2Satellite Units:Comprised of the following components:

.1Full-range, wide-dispersion loudspeaker.

.2Metal enclosure and mounting hardware.

.3Electrical connections.

.3Transformers: If not built into each master unit, provide separate [115 V] [ V] primary to low voltage (typically 18 V) AC secondary transformers, as required to power units.

3.Execution

3.1INSTALLATION

.1Install system components above suspended ceiling in accordance with manufacturer's instructions and in a manner that will permit specified acoustical performance requirements to be met.

.2Suspend sound masking units with mounting chains securely fastened to underside of structure. Ensure that there is no strain on any electrical wiring. Avoid mounting which could result in generation of vibration noise or distortion.

3.2TESTING, ADJUSTING, AND BALANCING

.1Comply with requirements of Section 260820 - Electrical starting and Testing by Contractor.

OR

SPECNOTE: Delete previous paragraph and specify following if sound masking is a separate contract and Section 260820 is not being used. Section 260820 contains the identical requirements.

.1Calibrate measuring microphone and related test equipment prior to testing.

.2In areas receiving sound masking,test, adjust, and balance system with mechanical ventilation system [off] [on minimum air flow] and any significant noise-generating equipment shut down.

.3Test, adjust, and balance system until sound spectrum and levels meet specified performance requirements.

.4Upon completion of tests, perform walk-through verification of areas to be covered by sound masking. Adjust settings of installed units, relocate installed units, or add additional units, and retest areas having abnormal characteristics or levels.

.5Tests and Test Methods:

.1Test to determine octave band sound pressure levels: take minimum of one reading for each master unit within master unit's coverage area.

.2Test to determine spatial average overall A-weighted sound pressure levels: take minimum of one reading for each enclosed room covered by sound masking and minimum of one reading per 20 m2 of floor area in all open spaces covered by sound masking.

.3Position of Measuring Microphone:1200mm above floor and minimum 1m away from any sound reflecting surface, in locations representative of each area to be sound masked.

.6Measure Sound Pressure Levels using the Equivalent Continuous Sound Level (Leq) mode for a minimum interval of 15 seconds using a manual sweep at each location.

.7Test Equipment:

.1Sound Level Meter:to ANSI S1.4, Type 1 or better.

.2Octave Band Filter:to ANSI S1.11, Class II or better.

.3Accuracy of Acoustic Calibrator:within ±0.3 dB at 25°C.

3.3SCHEDULE

SPECNOTE: Unless indicated on drawings, schedule locations where sound masking is required.

.1Provide sound masking coverage in the following rooms and areas:

.1[].

.2[].

.3[].

END OF SECTION

2010-11-15 BMS Version