Tham khảo tài liệu 'noise and vibration control episode 9', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | TM 5-805-4 AFJMAN 32-1090 the manual and it would not be discriminatory or unreasonable to specify that any purchased equipment for a particular building be required not to exceed the estimated values given here for that equipment. This is especially true if the actual acoustic design of a wall or floor or room treatment is dependent upon one or two particularly noisy pieces of equipment. A noise specification would not be necessary for relatively quiet equipment that does not dictate noise control design for the MER or the building. a. Waiver. If a noise level specification is required to be met for a particular piece of equipment and this becomes a hardship on the manufacturer or the owner in terms of cost or availability the noise specification could be waived depending on the response of all the bidders. If some bidders agree to meet the specification while others do not this could be a valid basis for selecting the quieter equipment. If no bidders can meet the specification the specification can be waived but it may be necessary to reevaluate the noise control requirements of the MER if this particular equipment is so noisy that it is responsible for the noise design in the first place. Of course it is the primary purpose of this manual to prevent just such situations as this as too many waivers would negate the value of the noise evaluation as a part of the design phase of the building. If the equipment measured for this study represents a fair sampling it is likely that most of the equipment would meet a noise specification. b. Sample specifications. The sample noise level specifications given below offer a broad set of procedures and suggestions for specifying noise data SPL or PWL on any desired piece of equipment. This is not offered as a standard for noise measurements however. Any acceptable and applicable measurement and specification procedure recommended by an appropriate standards group such as ANSI ISO AStM IEEE ASHRAE or others may be used as a .
