Abstract
Household appliances are widely used in daily life, and their safety performance is crucial. This article explores the application of rapid testing in the quality and safety supervision of household appliances in Shenzhen, focusing on aspects such as the rapid testing process, testing items, testing equipment, and on-site testing operations. It analyzes the problems encountered in the application of rapid testing and proposes solutions, providing references for the promotion and application of rapid testing for household appliances.
Keywords
Household appliances; Rapid testing; Safety
Introduction
Rapid testing refers to a set of testing methods characterized by speed, simplicity, strong on-site operability, low testing costs, and low technical requirements for testers. Rapid testing technology has been widely applied in the field of food safety supervision. Its simple operation, short testing time, and high sensitivity allow for comprehensive rapid testing throughout the food production, processing, and consumption processes, enabling early detection and resolution of problems, thus playing an important role in food safety supervision. Drawing on the rich experience accumulated in rapid testing for food safety in Shenzhen in recent years, in 2022, the Market Supervision Administration of Shenzhen City, Guangdong Province, explored a new model of “rapid testing + management and service” for industrial products, taking the lead in the country to integrate on-site rapid testing and supervision, case handling, and service work in the field of industrial product quality. To support this pilot work, the author’s department was responsible for developing rapid testing schemes, testing item development, and on-site implementation for household appliances. This article introduces the innovative application of rapid testing in the safety and quality supervision of household appliances, summarizes the experiences and shortcomings from the pilot work, and proposes improvement suggestions for future work, aiming to promote the efficiency, standardization, and scientific nature of rapid testing and provide reliable technical support for household appliance safety supervision.
1 Current Situation of Household Appliance Quality Supervision
Household appliances are the most frequently encountered consumer goods for the public and are indispensable in daily life. They are characterized by frequent use, a wide variety of products, and rapid updates and replacements. Quality issues in these products are related to the safety of people’s lives and property. National and local market supervision departments have included household appliances in the scope of supervision and random inspection, aiming to continuously improve the overall quality of these products by identifying quality issues in the production and circulation sectors. However, considering the long completion cycle of the supervision and inspection system, the high investment of human and financial resources, the cumbersome work processes, and the limitations on the number of product batches, it is necessary to add new regulatory models based on traditional supervision and inspection to promote product quality and safety supervision more flexibly.
2 Rapid Testing of Household Appliances
2.1 Overview of the Rapid Testing Process
The Shenzhen Market Supervision Administration has developed a clear and specific rapid testing process for industrial product quality. The administration issues rapid testing tasks and disseminates notifications for industrial product rapid testing. Rapid testing institutions develop operational procedures based on practical circumstances, clarifying work principles and operational requirements to standardize rapid testing practices and ensure quality and quantity in completing rapid testing tasks. Upon receiving a task, the rapid testing institution assigns testing engineers to carry portable testing equipment into high-risk areas such as hardware stores, small supermarkets, and markets within urban villages, where product safety issues are prominent and supervision is weak. They issue relevant notification documents to operators, communicate fully, and explain the rapid testing mechanism to ensure cooperation in the rapid testing work.
Testing personnel randomly sample products, adhering to the principle of minimally damaging samples while efficiently identifying quality issues. If a sample is damaged or its usability is affected during on-site testing, they will pay the merchant for the sample; otherwise, the merchant will provide the sample for testing free of charge, with the sample returned after testing. During on-site testing, testing engineers set up testing equipment in the store or in an open area outside. Due to the complexity of the on-site environment, some equipment requires power, and safety precautions must be taken during testing. Samples are tested, and testing records and results are documented.
Rapid testing is easy to implement, with portable equipment that is convenient to carry, simple to operate, and fast, typically yielding results within 30 minutes. The results are printed on-site, with compliant result reports kept by the rapid testing institution and non-compliant reports issued in triplicate to the tested unit, the rapid testing institution, and the local regulatory office. Non-compliant reports are not considered legal evidence but serve as leads for enforcement inspections.
2.2 Rapid Testing Products and Equipment
Based on the common products with high non-compliance rates published by provincial and municipal market supervision administrations, as well as consumer concerns, suitable household appliances for rapid testing include: electric fans, hair dryers, electric kettles, rice cookers, and induction cookers.
Considering the need for portable equipment and ease of on-site operation, the instruments for rapid testing of household appliances include: size and weight measuring instruments (calipers, electronic scales), input parameter measuring instruments (portable AC power supplies, electrical parameter meters), mechanical strength measuring instruments (spring impact testers), stability measuring instruments (digital angle gauges), and protective and mechanical hazard testing tools (Type B test probes, Type 13 test probes).
2.3 Analysis of Rapid Testing Items and On-Site Testing Methods
Testing items that are less affected by environmental conditions, convenient for on-site testing, and commonly associated with non-compliance are selected as rapid testing items. The analysis of relevant items and testing methods is as follows:
2.3.1 Verification of CCC Certificate Validity
This item primarily checks for the presence of the CCC mark and verifies the status of the CCC certificate. On-site testing method: All household appliances subject to this rapid testing are within the CCC directory. Inspect whether the product and its packaging have the correct CCC mark. For the verification of CCC validity, testing personnel log into the National Certification and Accreditation Information Public Service Platform to verify the status of the CCC certificate, accurately recording the results on the rapid testing report.
2.3.2 Labels and Instructions
This item mainly checks whether the use of labels is standardized, symbols are correct, and the content of the instructions and materials is complete. On-site testing method: According to GB4706.1-2005 and GB4706 Part 2, visually inspect the main body and the content of the instructions, including:
- Whether the main body is labeled with the model, rated parameters, manufacturer information, and whether II-class appliances are marked with the recycling symbol.
- Whether the unit symbols comply with the International System of Units.
- Whether a user manual is provided, and whether the installation and maintenance information in the manual is complete, including instructions for replacing the power cord if damaged.
- Whether the text in the manual and nameplate includes simplified Chinese, and does not only contain English or traditional Chinese.
2.3.3 Protection Against Access to Live Parts
This item is a key assessment of product safety, aimed at preventing consumers from accessing live parts or ungrounded basic insulated components during use, which could lead to electric shock hazards. The assessment focuses on the structure of the appliance and whether the shell provides adequate protection against accidental contact with live parts.
On-site testing method: The objects of protection against electric shock mainly include live parts, internal wiring, and ungrounded motor housings. With the advancement of technology and improvements in production levels, protection against live parts in household appliances has become relatively robust. On-site testing must focus on areas where issues are likely to occur, such as:
- For hair dryers, apply a slight force to the Type 13 test probe to see if it can penetrate the grille at the air outlet and contact the internal heating element.
- For induction cookers, apply a force of 20N to the Type B test probe to verify if it can penetrate the cooling grille and access live parts inside the cooker.
- For electric fans, focus on the openings under the motor cover and the openings in front of the motor after removing the protective cover, applying a force of 20N with the Type B test probe to verify if it can touch the ungrounded metal housing of the motor.
2.3.4 Input Power and Current
Input power or current is a key parameter reflecting the performance of household appliances and is of significant concern to consumers. This item requires on-site measurement of the actual input power and current of the appliance to avoid dangerous discrepancies between the power supply and actual input. On-site testing method: Use a portable AC power supply, set the input voltage to the rated voltage, and operate the appliance under normal working conditions. Measure the stable state input power or current using an electrical parameter meter, calculate the deviation from the rated value, and verify if this deviation complies with GB4706.1-2005.
2.3.5 Stability and Mechanical Hazards
The stability item primarily tests whether non-fixed appliances intended for use on a surface have adequate stability to prevent tipping hazards. The mechanical hazard item assesses whether dangerous moving parts are reasonably placed and adequately protected to prevent harm to users and the surrounding environment. On-site testing method: For the stability test, focus on electric fans, using a digital angle gauge to measure the tilt angle of a 10° inclined plane to verify if the fan tips over. The mechanical hazard test mainly focuses on the blades of electric fans, induction cookers, and hair dryers, verifying if the protective grille can withstand penetration by the test probe.
2.3.6 Mechanical Strength
Considering that household appliances may experience collisions during use and transport, the mechanical strength item assesses whether products have sufficient strength to withstand impacts or collisions that may occur during normal use. On-site testing method: The appliance should be rigidly supported, and a spring impact tester should be used to impact each weak point on the outer casing with an energy level of 0.5J for three times. After testing, check for any damage that would cause non-compliance with the standards.
2.3.7 Specifications of Power Cords
Using power cords with plugs is a common method for connecting household appliances to power sources, and the specifications of these cords directly affect product safety. This item specifies the type and minimum nominal cross-sectional area of power cords. On-site testing method: Use an electronic scale to measure the weight of the appliance. If the weight exceeds 3kg, visually inspect the specifications of the power cord, ensuring that it must use IEC60227 Type 53 wire and not Type 52 wire, based on the rated current of the appliance.
3 Problems and Improvement Suggestions for Rapid Testing of Household Appliances
The variety of household appliances is vast, with varying quality. Currently, only five types of household appliances have undergone rapid testing, resulting in limited coverage. It is suggested that future work expand the range of products, especially those with high consumer concern and quality issues, to include more in the rapid testing product directory. Given the portability of testing equipment, the on-site environment, and practical testing operations, the current range of rapid testing items is relatively small. Some key tests related to electrical insulation and electric shock hazards, such as electrical strength, leakage current, and discharge testing, are not convenient to conduct. Additionally, the on-site testing environment temperature often fails to meet the standard requirement of 20±5°C. It is recommended to develop and acquire rapid testing vehicles equipped with essential safety testing devices that can be temperature-controlled for convenient rapid testing operations.
4 Conclusion
Designed as an ordinary household appliance, this product is priced under 300 yuan, making it potentially popular. During the design process, user diversity was considered, and efforts were made to offer a range of functions and corresponding price tiers, providing customers with more options. This product aims to solve minor issues in people’s lives while reducing costs, achieving functions such as foot massage and simultaneous drying of feet and slippers. The market is still in its infancy, with vast potential. In summary, the introduction of a foot dryer can facilitate people’s lives and address the inconveniences associated with traditional foot drying methods.