Review of ABCsTypicalBetterBest Absorb – Ceiling Tile AC NRC Average NRC ceiling not rated 0.50 – 0.60 Moderate AC ceiling – 0.80 High AC ceiling 180 – – 1.00 Block - Furniture Panels Height STC Low dividers < 54“ 15 Moderate dividers 60“ 20 High dividers > 72“ 25 Cover – Sound Masking Level, dBA HVAC, mechanical noise 35 – 50 dBA Sound Masking System 46 – 50 dBA Sound Masking System 46 – 50 dBA Comments AbsorbStandard ceilings with average NRC ratings are designed to control reverberation and sound level, and are not meant for open plan privacy applications. AC rated ceiling tile are specifically designed to perform effectively in reducing sound reflections off the ceiling between adjacent spaces. A high AC rated fiberglass ceiling tile is a robust ceiling choice. This is the least expensive approach to allow flexibility in the other choices BlockLow furniture panels are used to physically define an office space, but are too low to block conversations between seated occupants. Moderate height furniture panels are at least 60” high. Since a seated person’s ear height is about 48”, the effective barrier is only 1’ high. Tall furniture panels providing full cubicle enclosure are a robust choice. The entry ways should be staggered to avoid line-of-sight between cubicles. CoverWithout an electronic sound masking system, the background noise is entirely dependant on the level and content of the mechanical systems noise. HVAC noise is highly variable by system design, time of day, outdoor environmental conditions, etc. Since the architectural system is not robustly chosen, a sound masking system can be used to improve the speech privacy – but – it will require a masking level approaching the maximum acceptable level, and could become annoying. A well designed, installed and tuned electronic sound masking system will provide non-intrusive speech privacy at a moderate sound level. General Office - Open Plan % Confidential % Non-intrusive Privacy % Marginal Privacy % No Privacy © 2004 Armstrong World Industries, Inc.

Review of ABCsTypicalBetterBest Absorb – Ceiling Tile NRC Average NRC ceiling 0.50 – 0.60 Moderate NRC ceiling High NRC ceiling > 0.75 Block – Ceiling Tile CAC Block – Wall Partitions Height STC Low CAC ceiling < 30 Demountable system Floor-to-Ceiling < 30 Standard CAC ceiling 35 Demountable system Floor-to-Ceiling 35 High CAC ceiling 40 Fixed wall partition Floor-to-Slab > 40 Cover – Sound Masking Level, dBA HVAC, mechanical noise 30 – 40 dBA Sound Masking System 41 – 45 dBA Sound Masking System 41 – 45 dBA Comments AbsorbStandard ceilings with average NRC ratings are acceptable for small closed rooms. Since the wall partition is only floor-to-ceiling, the ceiling CAC needs to be at least equal to the partition STC. Ceilings with moderate NRC ratings are preferred for larger closed rooms. Since the wall is only floor-to-ceiling, the ceiling CAC needs to be at least equal to the partition STC. A combined high NRC and high CAC ceiling tile is a robust ceiling choice. This is the least expensive approach to allow for flexibility in the other system choices. BlockThis is a very poor performance for a wall system, which very likely means that there are sound leaks at the floor and ceiling intersections. This is expected normal performance for a typical demountable wall system. Since the wall partition is floor- to-slab, the ceiling CAC is only secondary if all penetrations through plenum are sealed. CoverWithout an electronic sound masking system, the background noise is entirely dependant on the level and content of the mechanical systems noise. HVAC noise is highly variable by system design, time of day, outdoor environmental conditions, etc. Since the architectural system is not robustly chosen, a sound masking system can be used to improve the speech privacy – but – it will require a masking level approaching the maximum acceptable level, and could become annoying. A well designed, installed and tuned electronic sound masking system will provide confidential speech privacy at a moderate sound level. General Office – Private Office % Confidential % Non-intrusive Privacy % Marginal Privacy % No Privacy © 2004 Armstrong World Industries, Inc.

Healthcare - Open Areas Review of ABCsTypicalBetterBest Absorb – Ceiling Tile AC NRC Average NRC ceiling not rated 0.50 – 0.60 Moderate AC ceiling – 0.80 High AC ceiling 180 – – 1.00 Block – Glass divider Height STC Low glass height < 36“ 15 Moderate glass height 60“ 20 High glass height > 72“ > 20 Cover – Sound Masking Level, dBA Cover – Music Level, dBA HVAC, mechanical noise 35 – 50 dBA Background Music 60 dBA Sound Masking System 52 dBA Background Music 60 dBA Comments AbsorbStandard ceilings with average NRC ratings are designed to control reverberation and sound level, and are not meant for speech privacy applications in small open spaces. AC rated ceiling tile are specifically designed to perform effectively in reducing sound reflections off the ceiling in small open spaces. A high AC rated fiberglass ceiling tile is a robust ceiling choice. This is the least expensive approach to allow flexibility in the other choices BlockLow glass dividers are used to physically define a reception desk or counter space, but are too low to block conversations especially with a standing person. Moderate height glass dividers are at least 60” high. These work well for seated persons since the ear and voice are at about 48”, but doesn’t work so well for standing persons. Tall glass dividers of at least 72” can provide speech privacy even for most standing people. Of course there will have to be some type of small opening to speak through. CoverWithout an electronic sound masking system, the background noise is entirely dependant on the level and content of the mechanical systems noise. HVAC noise is highly variable by system design, time of day, outdoor environmental conditions, etc. The architectural system is not robustly chosen, but a background music system can “somewhat” improve speech privacy. Unfortunately, music varies in content and level and as such can not consistently provide acceptable masking. A well designed, installed and tuned electronic sound masking system will provide non-intrusive speech privacy at a moderate sound level % Confidential % Normal Privacy % Marginal Privacy % No Privacy © 2004 Armstrong World Industries, Inc.

Review of ABCsTypicalBetterBest Absorb – Ceiling Tile NRC Average NRC ceiling 0.50 – 0.60 Moderate NRC ceiling High NRC ceiling > 0.75 Block – Ceiling Tile CAC Block – Wall Partitions Height STC Low CAC ceiling < 30 Demountable system Floor-to-Ceiling < 30 Standard CAC ceiling 35 Demountable system Floor-to-Ceiling 35 High CAC ceiling 40 Fixed wall partition Floor-to-Slab > 40 Cover – Sound Masking Level, dBA HVAC, mechanical noise 30 – 40 dBA Sound Masking System 41 – 45 dBA Sound Masking System 41 – 45 dBA AbsorbStandard ceilings with average NRC ratings are acceptable for small closed rooms. Since the wall partition is only floor-to-ceiling, the ceiling CAC needs to be at least equal to the partition STC. Ceilings with moderate NRC ratings are preferred for larger closed rooms. Since the wall is only floor-to-ceiling, the ceiling CAC needs to be at least equal to the partition STC. A combined high NRC and high CAC ceiling tile is a robust ceiling choice. This is the least expensive approach to allow for flexibility in the other system choices. BlockThis is a very poor performance for a wall system, which very likely means that there are sound leaks at the floor and ceiling intersections. This is expected normal performance for a typical demountable wall system. Since the wall partition is floor- to-slab, the ceiling CAC is only secondary if all penetrations through plenum are sealed. CoverWithout an electronic sound masking system, the background noise is entirely dependant on the level and content of the mechanical systems noise. HVAC noise is highly variable by system design, time of day, outdoor environmental conditions, etc. Since the architectural system is not robustly chosen, a sound masking system can be used to improve the speech privacy – but – it will require a masking level approaching the maximum acceptable level, and could become annoying. A well designed, installed and tuned electronic sound masking system will provide confidential speech privacy at a moderate sound level. Healthcare – Treatment Rooms % Confidential % Normal Privacy % Marginal Privacy % No Privacy © 2004 Armstrong World Industries, Inc.