1 Scope
This standard applies to all dental patient chairs, regardless of their construction and also regardless of whether they are operated manually or electrically or by other means, or as a combination of these.
It specifies requirements, test methods, manufacturer’s information, marking and packaging.
2 Normative References
The following documents contain provisions which, through reference in this standard, constitute provisions of this standard. For dated reference, subsequent amendments to, or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to research the latest editions of these references are applicable. For undated references, the latest edition of the document referred to applies.
GB 9706.1-1995 "Medical Electrical Equipment Part 1: General Requirements for Safety" (idt IEC 60601-1:1988)
ISO 8191-1:1987 "Furniture - Assessment of the Ignitability of Upholstered Furniture - Part I: Ignition Source: Smouldering Cigarette"
ISO 9687:1993 "Dental Equipment - Graphical Symbols"
3 Definitions
For the purposes of this standard, the definitions given in GB 9706.1 and the followingdefinitions apply.
3.1
Dental equipment
Furniture, machines, apparatus and accessories thereto, specially manufacturedand/or presented for the use of authorized persons in the practice of dentistry and/or its associated procedures.
3.2
Dental patient chair
(1) Item of dental equipment, provided with a range of movements, which is designed to support and position the patient for treatment.
(2) Permanently fixed or free-standing chair, adjustable in height and posture used for supporting a patient in the seated or supine position and having the means for positioning the head of the patient for dental treatment.
4 Classification
This classification applies to electrically operated dental patient chairs only.
4.1 According to type of protection against electric shock
Dental patient chairs are classified in accordance with GB 9706.1:
a) Class I equipment
Equipment in which protection against electric shock does not rely on basic insulation only, but which includes an additional safety precaution in such a way that means are provided for the connection of accessible conductive parts to the protective (earth)conductor in the fixed wiring of the installation in such a way that accessible conductive parts cannot become live in the event of a failure of the basic insulation.
b) Class II equipment
Equipment in which protection against electric shock does not rely on basic insulation only, but in which additional safety precautions such as double insulation or reinforced insulation are provided, there being no provision for protective earthing or reliance upon installation conditions.
4.2 According to degree of protection against electric shock
Dental patient chairs are only of type B equipment.
Type B equipment
Class I or II equipment, or equipment with an internal electrical power source providing an adequate degree of protection against electric shock, particularly regarding:
——allowable leakage currents;
——reliability of the protective earth connection (if present).
Type B equipment is, for example, suitable for intentional external and internal application to the patient, excluding direct cardiac application.
4.3 According to mode of operation
Dental patient chairs are a type of equipment with intermittent operation.
5 Requirements and Recommendations
Electrical requirements are only applicable to electrically operated dental patient chairs.
There are, however, general requirements in GB 9706.1 referred to, which are applicable
Foreword I
Introduction II
1 Scope
2 Normative References
3 Definitions
4 Classification
5 Requirements and Recommendations
6 Sampling
7 Testing
8 Manufacturer’s Information
9 Marking
10 Packaging
Annex A (Normative) Sequence of Testing
