Acoustics

Acoustic noise emission data allows you to assess noise levels for your data processing equipment.

Acoustic noise emission data on IBM® products is provided for the benefit of installation planners and consultants to help predict acoustical noise levels in data centers and other installations of information technology and telecommunications equipment. Such noise declarations also allow you to compare noise levels of one product to another and to compare the levels to any applicable specifications. The format of the data provided conforms to ISO 9296: Acoustics - Declared Noise Emission Values of Computer and Business Equipment. The measurement procedures used to acquire the data conform to International Standard ISO 7779 and its American National Standard equivalent ANSI S12.10. The following terms are used to present acoustical data.

L_WAd is the declared (upper limit) A-weighted sound power level for a random sample of machines.
L_pAm is the mean value of the A-weighted sound pressure levels either at the operator position or at the bystander (1-meter) positions for a random sample of machines.
<L_pA>_m is the mean value of the space-averaged sound-pressure-emission levels at the one-meter positions for a random sample of machines.

Acoustical treatment of data centers or other rooms, in which the equipment is installed, is recommended to achieve lower noise levels. Lower noise levels tend to enhance employee productivity and avoid mental fatigue, improve communications, reduce employee complaints, and generally improve employee comfort. Proper room design, including the use of acoustical treatment, might require the services of a specialist in acoustics.

The total noise level of an installation with information technology and telecommunications equipment is an accumulation of all the noise sources in the room. This level is affected by the physical arrangement of the products on the floor, the sound reflective (or absorptive) characteristics of the room surfaces, and the noise from other data center support equipment such as air conditioning units and backup power equipment. Noise levels might be reduced with proper spacing and orientation of the various noise-emitting equipment. Provide sufficient space around such machines: the farther apart they can be placed, the lower the overall room noise will be.

In smaller installations, such as small offices and general business areas, pay additional attention to the location of equipment relative to the work areas of the employees. At work areas, consider locating personal computers and computer workstations next to the desk rather than on top of it. Small servers should be located as far away from personnel as possible. Locate nearby work areas away from the exhaust of computer equipment.

The use of absorptive materials can reduce the overall noise level in most installations. Effective and economical sound reduction can be achieved by using a sound-absorptive ceiling. The use of acoustically absorbing free-standing barriers can reduce the direct noise, increase room absorption and provide privacy. The use of absorptive material, such as carpeting on the floor, results in further reduction of the sound level in the room. Any carpeting used in a computer room must meet the electrical continuity requirements stated in Static electricity and floor resistance. To prevent computer room noise from reaching adjacent office areas, walls should be constructed from the structural floor to the structural ceiling. Also, ensure that doors and walls are properly sealed. Acoustical treatment of overhead ducts might further reduce noise transmitted to or from other rooms.

Many IBM large systems products are offered with optional acoustical front and rear doors to help attenuate the noise of the product itself. Smaller IBM products might also offer special acoustical packages. If noise exposure is a concern for the installation planners or employees, inquiries should be made to IBM on the availability of such product options.