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GB 21748-2008 English PDF

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GB 21748-2008: Safety requirement for the educational equipment -- Basic requirements for equipment and spare parts
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JY/T 0587   GB 21027   GB/T 37624   GB 21749   GB/T 21747   GB 21746   

Basic data

Standard ID GB 21748-2008 (GB21748-2008)
Description (Translated English) Safety requirement for the educational equipment -- Basic requirements for equipment and spare parts
Sector / Industry National Standard
Classification of Chinese Standard Y51
Classification of International Standard 03.180
Word Count Estimation 38,313
Date of Issue 2008-05-05
Date of Implementation 2008-08-01
Quoted Standard GB 1002-1996; GB 2099.1; GB 2099.2; GB/T 2887-2000; GB 2893-2001; GB 2894-1996; GB 4208-1993; GB 4343.2; GB 4706.1; GB 4706.19; GB 4706.52; GB/T 4723; GB/T 4724; GB/T 4725-1992; GB 4943-2001; GB 5083-1999; GB 6566; GB 6675-2003; GB 6829; GB 7000.1-2002; GB 7000.10; GB 7247.1-2001; GB/T 7261; GB/T 7450; GB 8898-2001; GB 9175-1988; GB/T 9239.1; GB 9254; GB 9364.6; GB 9816; GB 10320; GB 10434; GB 11806; GB/T 11918-2001; GB 12158; GB 13028
Regulation (derived from) Announcement of Newly Approved National Standards No. 7 of 2008 (No. 120 overall)
Issuing agency(ies) General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China
Summary This Chinese standard specifies the schools and training institutions classroom and laboratory instruments and components safety and quality requirements as well as mechanical properties, high and low temperatures, noise and vibration, ionizing radiation, non-ionizing radiation and electrical safety of the appended claims. This standard relates only to teaching instrument without involving other parts of the security features, such as design and features. This standard applies to schools and training institutions classroom and laboratory instruments and components.

GB 21748-2008: Safety requirement for the educational equipment -- Basic requirements for equipment and spare parts


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Safety requirement for the educational equipment.Basic requirements for equipment and spare parts ICS 03.180 Y51 National Standards of People's Republic of China Teaching instruments and equipment safety requirements The basic requirements for equipment and spare parts Posted 2008-05-05 2008-08-01 implementation Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China Standardization Administration of China released

Table of Contents

Introduction Ⅲ 1 Scope 1 2 Normative references 1 3 Terms and definitions 3 4 safety and quality requirements 3 4.1 Basic requirements 3 Raw materials 4 4.2 5 teaching instrument 5 Additional requirements for mechanical properties 5.1 Control and adjustment member 5 5.2 Structure 5 5.3 vibration and shock 6 5.4 Rotate the instrument 6 5.5 6 fastener 5.6 Quality Limit 7 5.7 acute angle, flash 8 5.8 signs and instructions 8 5.9 8 guards 5.10 9 non-normal operation mode 5.11 Inspection and maintenance 9 6 9 Additional requirements for high and low temperatures 6.1 High Temperature 9 6.2 cryogenic 9 Electrical Equipment 6.3 high and low temperatures under 10 7 Additional safety requirements for noise and vibration 10 7.1 Noise 10 10 7.2 Vibration 7.3 to reduce noise and vibration requirements 10 8 Ionizing Radiation Safety additional requirements 10 8.1 Ionizing Radiation Protection 10 8.2 use of radioactive materials in teaching equipment 11 8.3 radioactive dose limit 11 8.4 ionizing radiation monitoring 12 8.5 Several examples 12 8.6 Ionizing Radiation Safety warning signs 13 9 Additional safety requirements for electromagnetic radiation 13 9.1 Basic Requirements 13 9.2 laser light source 13 9.3 non-laser light source 14 10 15 Additional requirements for electrical safety 10.1 Electrical insulation, clearances, creepage distances and protective earth 15 10.2 pairs of contactless power protection 16 10.3 switches, control and regulating means 18 10.4 The main components 19 10.5 electric light and the electric heater 20 10.6 Environmental Impact 20 10.7 instrument rated running state 21 11 colors and logo Additional requirements 21 11.1 LEDs, buttons, wires, electrodes and the magnetic poles 21 22 11.2 Security warning signs 11.3 23 flags and signs Additional criteria in Appendix A (normative) use of protective measures and the use of lasers Class 3A, 3B and Class 4 laser class 25 The maximum exposure to ultraviolet radiation Appendix B (normative) allowed 27 Annex C (normative) visible light and infrared radiation exposure limits 28 Protection Appendix D (normative) UV, infrared, radio-frequency radiation of 30 Appendix E (normative) to reduce noise and anti-vibration 32

Foreword

The standard Chapter 4, Chapter 5, Chapter 6, Chapter 7, Chapter 8, 9, Chapter 10 and Chapter 11 are mandatory, the rest are pushed Recommended sex. The Standard Appendix A, Appendix B, Appendix C, Appendix D and Appendix E are normative appendix. The standard proposed by the People's Republic of China Ministry of Education. This standard by the National Standardization Technical Committee Instrument Teaching. This standard was drafted. Zhejiang Educational Equipment and work-study program management center, the Ministry of Education, Institute of Education and other equipment. The main drafters of this standard. Ren Weide, Zhao Liping, Zhao Xiang. Teaching instruments and equipment safety requirements The basic requirements for equipment and spare parts

1 Scope

This standard specifies the safety and quality requirements for schools and training institutions classroom teaching and laboratory instruments and parts and mechanical Can additional requirements are high and low temperatures, noise and vibration, ionizing radiation, non-ionizing radiation and electrical safety. This standard relates only teaching instrument zero The security element without involving other characteristics, such as characteristic and style. This standard applies to schools and training institutions classroom teaching and laboratory equipment and spare parts.

2 Normative references

The following documents contain provisions which, through reference in this standard and become the standard terms. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to the agreement are based on research Whether the latest versions of these documents. For undated reference documents, the latest versions apply to this standard. GB 1002-1996 Household and similar single-phase plug and socket type, basic parameters and dimensions GB 2099.1 plugs and sockets for household and similar purposes - Part 1. General Requirements (GB 2099.1-1996, eqv IEC 60884- 1.1994) GB 2099.2 plugs and sockets for household and similar purposes Part 2. Particular requirements (GB 2099.2-1997 appliance outlets, eqv IEC 60884-2-2. 1989) GB/T 2887-2000 General specification for computer sites GB 2893-2001 Safety colors (neq ISO 3864. 1984) GB 2894-1996 Safety Signs (neq ISO 3864. 1984) GB 4208-1993 shell protection (IP code) GB 4343.2 EMC household appliances, electric tools and similar apparatus - Part 2. Immunity - Product family standard (IdtCISPR14-2-97) GB 4706.1 Household and similar electrical appliances - Part 1. General Requirements (GB 4706.1-2005, idt IEC 60335-1. 2004) GB 4706.19 special requirements of household and similar electrical appliances for heating liquids (GB 4706.19-2004, idt IEC 60335-2-15.2000) Particular requirements GB 4706.52 Household and similar electrical appliances commercial electric cooking ranges, ovens, hobs and hob elements (GB 4706.52 -2001, Idt IEC 60335-2-36.1993) GB/T 4723 printed circuits copper clad phenolic paper laminate (GB/T 4723-1992, neqIEC 249-2. 1985) GB/T 4724 printed circuits copper clad epoxy laminate paper (GB/T 4724-1992, neqIEC 249-2. 1987) GB/T 4725-1992 printed circuits copper clad epoxy glass cloth laminate (neqIEC 249-2. 1987) GB 4943-2001 Safety of information technology equipment (eqv IEC 60950.1999) GB 5083-1999 General production equipment with safety and health GB 6566 building materials radionuclide limits GB 6675-2003 National Safety Technical Code for Toys GB 6829 General requirements for residual current operated protective devices GB 7000.1-2002 General safety requirements and test fixtures (idt IEC 60598-1.1999) GB 7000.10 Safety requirements for fixed general purpose luminaires (GB 7000.10-1999, idt IEC 60598-2-1. 1979) GB 7247.1-2001 Safety of laser products - Part 1. Equipment Classification, Requirements and User's Guide (idt IEC 60825-1. 1993) Basic testing method GB/T 7261 relay and equipment GB 7450 Guidance for lightning protection of electronic equipment GB 8898-2001 Audio, video and similar electronic apparatus - Safety requirements (eqv IEC 60065.1998) GB 9175-1988 environmental electromagnetic health standards GB/T 9239.1 Mechanical vibration steady state (rigid) rotor balance quality requirements - Part 1. Specification and balance tolerance test (GB/T 9239.1-2006, idt ISO 1940-1.2003) GB 9254 Limits and methods of measurement of radio disturbance of information technology equipment (GB 9254-1998, idtCISPR22.1997) GB 9364.6 Miniature fuses - Part 6. Fuse holder Small cartridge fuse (GB 9364.6-2001, idt IEC 60127- 6.1994) GB Requirements and application guide 9816 of the thermal fuse (GB 9816-1998, idt IEC 691.1993) GB 10320 Electrical safety of laser equipment and installations GB 10434 workplace hygiene standards of local vibration GB 11806 safety of radioactive material transport regulations GB/T 11918-2001 industrial plug and socket couplers - Part 1. General requirements (idt IEC 60309-1.1999) GB 12158 General guidelines for preventing electrostatic accidents GB 13028 safety transformer isolation transformer and technical requirements GB 13539.1 low-voltage fuses - Part 1. General requirements (GB 13539.1-2002, idt IEC 60269-1.1998) GB 13539.3 low-voltage fuses - Part 3. Non-cooked refining personnel Supplementary requirements for fuses (mainly used for household and class Like the use of fuses) (GB 13539.3-1999, idt IEC 60269-3. 1987) GB 14050 type of system grounding and safety technical requirements GB 14196.1 domestic and similar general lighting purposes - Safety requirements GB 14196.2 domestic and similar general lighting purposes - Safety requirements for tungsten halogen lamps GB/T 14472 Fixed capacitors for use in electronic equipment - Part 14. Sectional specification Fixed electromagnetic interference suppression capacitors (GB/T 14472-1998, idt IEC 60384-14.1993) GB/T 14623 urban regional environmental noise measurement method GB 15092.1-2003 Switches for appliances - Part 1. General requirements (idt IEC 61058-1.2000) GB 15219 transport of radioactive material packaging quality assurance GB 16179 the use of safety signs GB 17285 electrical equipment power rating marking safety requirements (GB 17285-1998, idt IEC 1293.1994) The first part of the GB 17465.1-1998 appliance couplers for household and similar purposes. General requirements The second part of the GB 17465.2-1998 appliance couplers for household and similar purposes. Household and similar equipment interconnection couplers GB/T 17618 Information technology equipment - Immunity characteristics - Limits and methods of measurement (GB/T 17618-1998, idtCISPR24.1997) Limits and methods of measurement of radio disturbance characteristics of GB 17743 electrical lighting and similar equipment GB/T 18153-2000 Safety of machinery - accessible surface temperature Ergonomics data to establish temperature limit values for hot surfaces GB 18217-2000 Laser Safety Signs GB/T 18268 for measurement, control and laboratory use electrical equipment electromagnetic compatibility requirements (GB/T 18268-2000, idt IEC 61326-1. 1997) GB 18528-2001 workplace ultraviolet radiation occupational exposure limits GB 18581 interior decoration materials, solvent-based coatings of harmful substances GB 19652 discharge lamps (excluding fluorescent lamps) - Safety requirements (GB 19652-2005, idt IEC 62035.1999) GB 21746-2008 Safety requirements General Teaching Equipment GB 50222-1995 interior decoration of buildings for fire protection design

3 Terms and Definitions

The following terms and definitions apply to this standard. 3.1 In order to prevent leakage of electrical equipment, grounding occurs when human contact metal frame or electric shock carried out. NOTE. Ground wire English name for protectiveearthingconductor, usually abbreviated PE line. "Ground" refers to a special device for big Ground. Protective grounding applies to ungrounded low-voltage grid. 3.2 Neutral grounding grid, in order to prevent a single relatively large current, protective earth can not completely avoid the risk of electric shock the body, The metal frame or zero line and grid connected electrical equipment. Note. The "zero line" also known as "neutral."

4 safety and quality requirements

4.1 Basic requirements 4.1.1 classroom teaching, teaching equipment and components used in training (hereinafter referred to as "teaching machines") have been determined under the same standard conditions Temper Justice of the safety requirements for the use of appropriate safety standards, safety requirements priority contradiction in safety requirements and the economic interests of Etc. according to GB 21746-2008. 4.1.2 teaching equipment and parts product design of the structure and use of raw materials should be considered acts of users of different ages, the responding party Style, intelligence and capabilities; users should also consider the use of human data object and scope and can be expected at that age or Other users misuse. If necessary, the product standard shall specify the applicable age and use restrictions. To fully consider the different ages of students Psychological and physiological characteristics, so that safety, health, application, beautiful. 4.1.3 Teaching instruments and components should be considered for use in a variety of the most adverse situations that may arise can maximize the protection of safety, the junction Structure should be designed to avoid dangerous situations or to the degree of risk occurrence minimize shall direct, indirect or direct security technology, including direct Security technology has the greatest priority. If, for the needs of teaching and other technical reasons can not achieve effective security and protection must be provided to avoid Free use of the operating instructions and danger warnings. 4.1.4 determine what design, should follow the priorities 4.1.5. Wherein the elimination, prevention and mitigation of direct safety technology Surgery, isolation and security technology is an indirect interlock, warning prompted security technology. 4.1.5.1 ~ 4.1.5.5 shall not take into account the technical measures used only informative technical safety measures. 4.1.5 Security Technology 4.1.5.1 Elimination Through rational planning, design and scientific management as a fundamental source to eliminate hazards. Such as the use of raw materials and harmless harmless experiment Party Method. 4.1.5.2 Prevention When the source is difficult or eliminate the hazard can not completely eliminate the hazard source, technology should adopt preventive measures to prevent harm occurring. Such as the use of melt Off, safety valves and the like. 4.1.5.3 weaken In the case of hazards can not be eliminated source and difficult to prevent, and should be used to reduce the harm of measures, such as the use of low toxic substances instead of the highly toxic substance Quality, limiting the radiation dose and the like. 4.1.5.4 Isolation In can not be eliminated, prevention and mitigation of the situation, measures should be adopted to harm people and isolate the source, such as the use of shields, shield and so on. 4.1.5.5 Interlocking Where possible, the interlock device should be used, so that in the event of operator error or equipment operation reaches a dangerous state, interlock Run the risk of termination. 4.1.5.6 Warning Fault and a larger risk-prone areas, or after taking the above measures residual danger remains, configure striking Identify warning signs, if necessary, use sound, light or sound and light signals. 4.1.6 When considering the safety performance of teaching equipment, analyzing various possible causes dangerous not only to take into account in accordance with the intended use and the positive Often used, but also taking into account the reasonably foreseeable misuse. Note. The "intended use", the definition of "normal use" and "reasonably foreseeable misuse" see GB 6675-2003 in A. 3. 4.1.7 Teaching instruments and components used should be in accordance with the appropriate severity level of the specified instrument proper safety and make the appropriate test. 4.1.8 teaching instrument signals used to avoid the following drawbacks. a) lack of signal facilities (for example, to indicate power on, the instrument normal operation and failure, etc.); b) the improper selection signal; c) improper position signal; d) signal is unclear; e) are not allowed to display signal (not correctly reflect the status of the instrument). 4.1.9 display section Classroom demonstration instrument display and scale display member, distinguished observation distance of not less than 9m; students test instrument display And scale display member, distinguished observation distance of not less than 0.3m. 4.2 raw materials 4.2.1 General requirements Products for the raw material, its physical and chemical properties and should meet the design requirements, the performance and quality of raw materials and manufacturers Consistent. 4.2.2 Hazardous Materials Materials used does not produce any harmful effects on the human physiology. If not reach this requirement, it should be in the order of 4.1.5 Safety technical measures. Hazardous materials include. a) the contaminated material. Filler 1) teaching the instrument should not use the waste material by chemical or biological contamination, contain harmful chemicals or heavy metals over Subject material, can produce harmful dust or fiber material after damage, flammable materials, materials containing eggs and other harmful substances; 2) teaching the instrument to avoid bacteria, viruses, pathogenic microorganisms or other infectious diseases vehicle pollution, and should avoid using virulence Injuring animals or plants; 3) with medical equipment as a teaching experiment, the hospital should not be used used obsolete equipment. The new equipment should be used with Equipment intact original packaging. b) teaching equipment coatings heavy metal limits should be consistent with GB 18581. c) painting equipment, paint, chemical toys and pencils (including mechanical pencil lead core), crayons, chalk limits of heavy metals should be consistent GB 6675-2003 Appendix C (normative). According to GB 6675-2003 Appendix C of the test method. 4.2.3 anti-aging material Any instrument due to material aging may cause slow performance and affect the safety of the site should be used in anti-aging capabilities have enough material. 4.2.4 high temperature, low temperature and non-combustible material Materials used equipment 4.2.4.1 generate heat when not working due to high temperature heat source to melt, bending, loss of strength or fire, or make Used at high temperatures carbonized organic material; at operating temperature and the protective layer coating should not cause damage. Should not be used at low temperatures perishable, fragile materials. 4.2.4.2 teaching equipment shall be non-combustible materials or fire-retardant materials, in addition to functional needs, flammable materials should not be used as a teaching instrument for structural lumber material. Should not be used the following materials. a) nitrocellulose or material having the same characteristics in the fire; Note. The above "same characteristics" does not include paints and varnishes. b) instantaneously ignited fluff material close to the fire source; c) flammable gas can not be used pneumatic; d) After the flame spread rate is greater than 50mm/s, or longer than 10s combustion of materials. 4.2.5 corrosion-resistant material Any instrument due to corrosion that may affect the safety of the site should be used in sufficient corrosion resistance of the material, or otherwise taken sufficient The anti-corrosion measures. 4.2.6 material strength Safety Factor teaching instrument timber (including metallic materials and non-metallic materials) shall not be less than production equipment. 4.2.7 Use of unsuitable materials a) aging, after damage to produce materials harmful substances (such as. glass fiber - epoxy composites); b) for equipment used independently of students, in addition to very necessary, as far as possible without the glass material. You must use the glass as a material When the equipment, there should be flexible packaging, where possible, should the case with other glass-reinforced material to prevent crushing or breaking and Specification shall prevent the glass broken equipment wounding warning instructions; c) When using glass materials, should be adopted without dazzling and unbreakable glass; d) for children with equipment, toys or equipment, should not food (including food taste) mix. Note. The above "try" means whenever possible, it should do so, the same below. 4.2.8 eliminate or reduce material deterioration factors According to material deterioration of the reason, in the design of the instrument should be selected and controlled. Means the instrument selection and use of environmental performance requirements Choice of material, control means taking measures to eliminate or reduce the deterioration of the material factors, extend the life of equipment and spare parts, or reasonably determined Life cycle and replacement equipment and parts, as well as to determine the required maintenance projects. 4.2.9 Other Material teaching the instrument shall comply with the 5.2 GB 5083-1999. Additional requirements for mechanical properties 5 teaching equipment 5.1 Control and adjustment member 5.1.1 Control adjustment member should not bring harm to users, the regulatory function should be clearly marked on the product in working condition. 5.1.2 various control operations should be durable and reliable components and switches, switches and knobs should be flexible rotation, jump clear, accurate positioning. 5.2 Structure 5.2.1 Instruments and various expandable and scalable structure should not have dangerous effects on the various instruments and associated projecting plate, sharp Angle edge. Fastening method 5.2.2 equipment and components should be reliable. 5.2.3 need to move product in hazardous situations for use, the handle should be made of the buried rather than drawing style. Position knob setting should not Other devices will be stuck, wire or protruding parts. In all possible cases, the handle should be set above the center of gravity. 5.2.4 Distribution of quality should be easy instrument handling, loading or positioning. 5.2.5 various safety valve, valve or other safety devices should be adjusted to its predetermined value. Xu 5.2.6 high speed rotating parts imbalance should be consistent with GB/T 9239. 5.2.7 Without prejudice to the use of performance, it is desirable to limit the quality and speed of moving parts, the operating force is limited to a minimum. 5.2.8 The instrument should be avoided when using or not using penetrating injuries caused due to failure risk factors, such as. a) due to sudden rupture of component materials; b) due to the small cross-sectional area of the parts popping; c) Within the scope of personnel to operate in other parts of the tip, accidentally hurt the operation; d) due to failure, the operation of other parts of parts or pop fly. When teaching equipment design certification and testing, should take into account all possible scenarios, analysis and test whether the presence of risk factors. 5.2.9 predetermined teaching toys into the mouth or element, if placed in 31.75mm truncated right cylinder × 57.15mm, and its structure should be So that when applied to 1 × 104Pa suction on the mouthpiece even said element is disengaged, can not be divorced toys. 5.2.10 manipulator, signal, display and control system according to GB 5083-1999 of 5.5 and 5.6. 5.3 vibration and shock 5.3.1 The equipment should be able to withstand without damage to its own vibration or shock, and encountered during transport vibration, shock or may encounter Other conditions to. 5.3.2 The instrument vibration generated during operation should not reach engender comfort level. Should be avoided by appropriate design Resonance frequency (avoid the resonance frequency of the request without resonance instrument). 5.3.3 anti-shock and anti-vibration device can only be used in the design or manufacture of the instrument difficult to meet the requirements specified in shock and vibration, or shock, vibration Non-destructive inertia may move or place. 5.3.4 damping apparatus should not in any other way except with a shock absorber designed to install. 5.3.5 cooling device or any other accessory device (such as cables, hoses and others) should not prevent damping bracket good work. 5.3.6 support, fixture, rail, cable clamps and mounting screws, etc., should be designed to lower the maximum acceleration (such as anticipated transport conditions Possible maximum acceleration) conditions prop mounted on the lower parts, and withstand accidental misuse by the situation. 5.4 Rotate the instrument 5.4.1 mounting frame rotary instruments should have sufficient rigidity and stability degrees. 5.4.2 mechanical connection with the operation of other devices should be installed to turn the instrument appropriate, to prevent damage to the connected equipment, couplings, install it Structure or other devices. 5.4.3 may be damaged by impact during operation or cause people to turn the instrument FOD should be equipped with at least two safety devices (Such as hard brakes, shock absorbers, buffers and vacuum or pneumatic flow restrictor). The instrument should automatically detect impending damage, and play Fixed backup safety device. Safety devices shall be installed by the test, ensure that it meets the requirements. 5.4.4 avoid fatigue in the variable component of stress (mainly cyclical stress), the rotary member should correct static balance and dynamic balance. 5.4.5 Parts 5.4.5.1 Under n...

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