Akustik och bullermätning

The proposed standard deals with cases where a vibrating component (a source of structure-borne sound

or vibration) is attached to a passive structure (or receiver) and is the cause of vibration in, or structureborne

sound radiation from, the assembly. Examples are pumps installed in ships, servo motors in

vehicles or machines and plant in buildings. Almost any vibrating component can be considered as a

source in this context.

It is necessary to measure vibration at all contact degrees of freedom (connections between the source

and receiver). Therefore, the standard can only be applied to assemblies for which such measurement is

possible.

The standard is restricted to assemblies whose frequency response functions (FRFs) are linear and time

invariant.

The source may be installed into a real assembly or attached to a specially designed test stand (as

described in 4.2).

The standard method has been validated for stationary signals such that the results can be presented in

the frequency domain. However, the method is not restricted to stationary signals and with appropriate

data processing it is also applicable to time-varying signals such as transients and shocks (provided

linearity and time invariance of the FRFs is preserved).

This standard applies to Hearing Aid Fitting Management (HAFM) services offered by hearing aid professionals (HAP) when providing benefit for their clients. The provision of hearing aids relies on the practices of a hearing aid professional, to ensure the proper fitting and adequate service in the interest of the client with hearing loss.

This standard specifies general processes of HAFM from the client profile to the follow-up through administering, organising and controlling hearing aid fitting through all stages. It also specifies important preconditions such as education, facilities, and systems that are required to ensure proper services.

The focus of this standard is the services offered to the majority of adult clients with hearing impairment. It is recognized that certain groups of hearing loss such as children, persons with other disabilities or persons with implantable devices may require services outside the scope of this standard.

Hearing loss can be a consequence of serious medical conditions. Hearing aid professionals are not in a position to diagnose or treat such conditions. When assisting clients seeking hearing rehabilitation without prior medical examination hearing aid professionals must be observant of symptoms of such conditions and refer to proper medical care.

Further to the main body of the standard, that specifies the HAFM requirements and processes, several informative annexes are provided. Proper education of hearing aid professionals is vital for exercising HAFM. Annex A defines the competencies required for the HAFM processes; Annex B offers a recommended curriculum for education of hearing aid professionals. Annex C is an example of an appropriate fitting room. Annex D is a guidance on referral of clients for medical or other specialist examination and treatment. Annex E is a recommendation for important information to be exchanged with the client during the course of HAFM. Annex F is a comprehensive terminology list offering definitions of most current terms related to HAFM.

It is the intention that these annexes will be helpful to those who wish to deliver HAFM of the highest quality.