Squealing
tires and screeching brakes-loud distracting noises, which are usually associated with a
race track or cross town travel. Not in this case, however. Inside a auto
assembly plant, employees just in a shiny new car fresh off the assembly line, accelerate
to 60 MPH and then stomp on the brakes. This is the first step in testing
accelleration and braking on new vehicles fresh off the assembly line, which are then
moved to an idle lane for additional tests. The auto manufacturer's policy of
creating and maintaining high standards of employee comfort and benefits led to a desire
to reduce the noise level exposure for workers in the surrounding area.
| After extensive
testing and analysis, engineers selected BSC-25 Acoustical Curtain Panels. As
opposed to some of the rigid, metal type of noise control products available in the
marketplace, flexible sound absorber/noise barrier composite products can offer maximum
accessibility, visibility and affordability, while still offering significant noise
reduction. It was recommended that three forty-foot long bays be created to seperate
the idle lane from the active lane. Acoustical Curtain Panel model BSC-25 combines a
quilted fiberglass sound absorber on both sides of a loaded vinyl noise barrier. The
modular curtain panels were fabricated with full width view windows, grommets at the top
with hook and loop fasteners along each edge to join adjacent panels together to form the
designed configuration. The BSC/full width view window panels are specifically
designed to offer complete visibility into the area along with effective sound absorption
and noise barrier characteristics. |
Click
photo to enlarge
.jpg) |
The BSC-25 Acoustical
Composite Curtain Panel satisfied the acoustical engineers requirements to provide
separator partition walls between each bay by utilizing a single product that would serve
as both a noise barrier material between bays as well as a sound absorption product within
each bay. In general, ASTM laboratory testing standards are utilized to determine
how effective various products perform regarding their ability to either absorb sound
waves, rated as "NRC", or block sound waves, rated as "STC". The
NRC (Noise Reduction Rating) of BSC-25 is .85. The STC (Sound Transmission
Classification) is 29. Since a heavy duty one pound per sq. ft. flexible transparent
vinyl noise barrier material is utilized as the view window section of the panels, there
is minimal, if any, loss of acoustical performance thru the window area.
A related Acoustical Curtain Panel,
BBC-13-2", was used as an "end cap" on one of the bays. Its purpose
was also to absorb and contain the noise. However, since these panels are in a high
abuse potential area where they drive the cars and move other equipment into the bays, the
BBC-13-2" Acoustical Curtain Panels are utilized becuse they have a very rugged,
durable reinforced noise barrier exterior and the quilted fiberglass sound absorber on the
interior side only.
Even with large open areas and an
open top, upon completion of the Acoustical Curtain Enclosure, employees noise exposure
dropped by 7dB(A) bringing these employees within acceptable noise exposure limits and
creating a better working environment for the auto manufacturer's employees.
|
