Section Cover Page
Section 16821
2003-08-06 Self-Contained Sound Masking Units

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

This Master Specification Section contains:

.1 This Cover Page

.2 Data Sheet – Reference Documents

.3 Specification Section Text:

1. General

1.1 Related Sections

1.2 Product Options and Substitutions

1.3 System Description

1.4 Performance Requirements

1.5 Submittals

1.6 Installer Qualifications

1.7 Performance Verification by Minister

1.8 Scheduling

2. Products

2.1 Proprietary Products

2.2 Components

3. Execution

3.1 Installation

3.2 Testing, Adjusting, and Balancing

3.3 Schedule

BMS Basic Master Specification
Alberta Infrastructure
Master Specification System / Page 0
Data Sheet - Reference Documents
Section 16821
2003-08-06 Self-Contained Sound Masking Units

Applicable Standards

.1 ANSI S1.4-1983(R1994) Sound Level Meters

.2 ANSI S1.11-1986(R1993) Octave-Band and Fractional Octave-Band Analog and Digital Filters

These reference documents may be available for reference purposes in the Technical Services Branch Library, 3rd Floor, Alberta Infrastructure, 6950 - 113 Street, Edmonton; Telephone:(780) 427-7924.

END OF DATA SHEET

BMS Basic Master Specification
Alberta Infrastructure
Master Specification System / Page 01
Section 16821
Plan No: Self-Contained Sound Masking Units
Project ID: Page 1

1. General

1.1 RELATED SECTIONS

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.

.1 Electrical General Requirements: Section 16010.

.2 Wire and Cable: Section 16121.

.3 Electrical Starting and Testing General Requirements: Section 16970].

OR

.1 Basic Electrical Requirements: Section 16005.

.2 Basic Electrical Materials and Methods: Section 16050.

.3 Electrical Starting and Testing General Requirements: Section 16970].

1.2 PRODUCT OPTIONS AND SUBSTITUTIONS

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

1.3 DESCRIPTION OF SYSTEM

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

.2 System 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.

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

1.4 PERFORMANCE REQUIREMENTS

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

.2 Octave Band Sound Pressure Levels:

Octave Band Centre
Frequency(Hz) / Average Sound
Pressure Level(dB) / Tolerances(dB)
125 / [46] [] / +44
250 / [43] [] / +22
500 / [39] [] / +11
1000 / [34] [] / +11
2000 / [27] [] / +11
4000 / [20] [] / +11
8000 / [12] [] / +32

.3 Spatial Average Overall Sound Pressure Level:Minimum [39] []dB and maximum [42] [] dB, Aweighted.

1.5 SUBMITTALS

.1 Comply with requirements of Section 16010.

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

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

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

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

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

1.6 INSTALLER 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.

1.7 PERFORMANCE VERIFICATION BY MINISTER

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

.2 Performance 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.

.3 Verification by the Minister will be performed with mechanical systems shut down in area being tested.

1.8 SCHEDULING

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

.1 Schedule 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.

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

2. Products

2.1 PROPRIETARY PRODUCTS

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

.1 Scamp Models PLM-6 and PLS-6, manufactured by K.R.Moeller Associates Ltd., Oakville, ON, and distributed by Sound-Rite Acoustics Inc., who may be contacted as follows:

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

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

.2 Plenum Series Models LM6 and LS6, manufactured by Lencore Acoustics Corp., and distributed by Vibra-Sonic Control and Materials Handling Ltd., Calgary, tel. (403) 217-3555; fax (403) 217-3547.

2.2 COMPONENTS

.1 Master Units:Comprised of the following components:

.1 Random noise generator.

.2 Amplifier with output gain adjustment.

.3 Adjustable lowpass filter or octave band equalizer.

.4 Loudspeaker.

.5 100% solid state circuitry.

.6 Metal enclosure and mounting hardware.

.7 Electrical connections.

.2 Slave Units:Comprised of the following components:

.1 Loudspeaker.

.2 Metal enclosure and mounting hardware.

.3 Electrical connections.

.3 Transformers: If not built into each master unit, provide separate [115 V] [ V] primary to 16 V AC secondary transformers as required.

3. Execution

3.1 INSTALLATION

.1 Install 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.

.2 Suspend 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.

3.2 TESTING, ADJUSTING, AND BALANCING

.1 Comply with requirements of Section 16971 - Electrical starting and Testing by Contractor.

OR

SPECNOTE: Delete previous paragraph and specify following if sound masking is a separate contract and Section 16971 is not being used. Section 16971 contains the identical requirements.

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

.2 Test, adjust, and balance system with mechanical system and other noise generating equipment shut down in areas receiving sound masking.

.3 Test, adjust, and balance system until sound spectrum and levels meet specified performance requirements. Adjust settings of installed units, relocate installed units, or add additional units, if and as required.

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

.5 Tests and Test Methods:

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

.2 Test to determine spatial average overall 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.

.3 Position 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.

.6 Measure Sound Pressure Levels using one of following methods:

.1 Equivalent Continuous Sound Level (Leq) mode for minimum interval of 15 seconds.

.2 IEC 651 'slow' time constant; average reading of the highest and lowest level during 15 second interval.

.7 Test Equipment:

.1 Sound Level Meter:to ANSI S1.41983, Type 1 or better.

.2 Octave Band Filter:to ANSI S1.111986, Class II or better.

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

3.3 SCHEDULE

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

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

.1 [].

.2 [].

.3 [].

END OF SECTION