Page 28 - Summer2019

Acoustic Comfort in Restaurants
at the possibility of writing such a standard, a.nd, to that _ _ A
. . .. . ,, Building Acoustic Standards
end, a special session on Restaurant Acoustics was spon-
sored by the ASA Panel on Public Policy‘ at the Boston
meeting. Since then, additional special sessions have been """"“"""""" """"""‘
offered and more test data have been collected, but what HIM", ma I ‘I Afliw
to do next? 9 laboratory mi: 4» Design cm-na
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The normal practice for the development of acoustic stan- -c- Field Vests ./ Ngjflhcgyglsl) 70)
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practice and ends with building codes and regulations. To « aw", d5|g_iV¢i([]574) 4 gas,” (rqgug
date, design knowledge for the acoustics of these spaces is 1 Room rsotzzzasi -/ KP Green Il|d5i(l!9.l)
. . . . ¢ spi-cm PIiv1ry(E1130] - IE0 Acoiisiizcomton
generally available to architects, engineers, designers, and
consultants, often based on research into the design practice
and performance as previously discussed. Design guidelines Figure 5. Measurement and performance standards for quantitative
for restaurants tend to be internally held by the owners. For apprnaeh. ASA/ANSI, Acnustieal Saciety nf America/American
instance, chain “fast food” restaurants such as McDonalds National Standards Institute; IEQ, indonr environmental quality.
and Burger King usually have model design standards for STC, sound transmission class rating; ASTC,field—measured apparent
their buildings. However, despite all the talk about “noisy STC; NRC. noise reduction eoeficient rating; NIC, noise isolation
is good for turnaround,” the fast food industry has certain class rating; HR high perfzrmanee; T60, reverlzeratiari time; ASHKAE.
model building specifications that include acoustic ceiling American Society of Heating, Refrigeration, and Air—Conditioning
tiles, usually i.n the form of 2-foot X 2-foot suspended ceilings. Engineers; terms in parentheses, actual test standard designation by
Although their first consideration is likely to be installation ASTMInternatinna1, ASA, or ASHRAE.
costs, accessibility, and esthetics, acoustics is being provided
in the suspended ceilings despite the contention that noisy
is good. Really? because all classrooms need a good listening environment
for students to learn from the teachers (Brill et al., 2018;
can We Quantify or Qualify Acoustic Comfort? Leibold et al., 2019), and so the focus is on speech intelli-
One can choose to address acoustic comfort in restaurants gibility. Additionally, many classrooms are architecturally
in either of two ways. The most obvious approach is to very similar in size and shape, making the acoustic needs
address the need for acoustic comfort in hospitality using relatively easy to define.
the same methods and metrics currently used in other
building segments, which would be a quantitative mode Restaurants, diners, and bars, on the other hand, have a list of
using measurement and performance standards. A second requirements including speech intelligibility, speech privacy,
but more qualitative mode would be to develop a classifica- annoyance, and entertainment, and within these, there is a
tion standard. range of conditions for each acoustic factor depending on
the type of establishment, time of day, or day of the week. So,
We certainly know how to go about accomplishing the first treating a restaurant in the same way as a school does not
option, and the tools for doing so are shown in Figure 5. make a whole lot of sense without addressing a very complex
set of requirements. Although it may be possible to develop
ASTM International is well-known for its portfolio of acous- a range of performance requirements for acoustic comfort in
tic measurement standards, and these are referenced in the the hospitality building segment, this may take a significant
ANSIIASA S12.60 standard for acoustics in classrooms, for level of research and “buy-in” from all the interested parties
example, where both measurement and performance stan- (owners, customers, and employees). This is why a previous
dards are applied. This is not ditficult to specify for schools attempt by ASTM International to take this approach was
not successful. Accordingly, we may wish to take a more
‘ See Sound Perspectives essay an ihis panel by Walsh in this issue a] Simiilistic aPPl’°3Ch J'“5‘ to SET Stmedi and ‘hen 599 Where
Acoustics Today. this may lead.
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