Abstract: This paper elucidates the importance of safety design in electronic products. Taking human-computer interaction interface design as an example, it elaborates on several principles and methods of safety design for electronic devices. Applying this design concept to the entire electronic product design process will help improve product quality. Keywords: Human-computer interaction interface, safety design, electronic products. In the Chinese market, domestically produced electronic products have consistently outperformed imported ones, although they often have advantages in terms of functionality or price. The fundamental reason for this is their inferior quality compared to imported products. Product quality encompasses not only performance but also reliability and safety. One reason for poor product quality is the lack of safety awareness during product design. Another reason is the "stormy development" model in the domestic market, which lacks verification and leads to the rapid launch of new products, often resulting in unintended consequences. To improve the competitiveness of domestically produced electronic products, it is essential to fundamentally improve product reliability and safety. Reliability and safety are distinct yet interconnected. Currently, there is abundant information on reliability design, which is deeply integrated into designers' thinking, while safety design has not been widely adopted. Safety is a quality of a system that allows it to function under acceptable minimum accident loss conditions; it is also defined as the ability to prevent accidents. For product development, designers need to possess a product safety design awareness. Safety design awareness here refers to considering and mitigating various potential safety hazards in product design (not only personal injury to users, but also system malfunctions). Safety design encompasses a wide range of content; this text only illustrates a few safety considerations from the perspective of user panel (human-computer interaction interface) design. Safety design is often a matter of systematic thinking and awareness. It is hoped that by using human-computer interaction design principles as an example, this can be integrated and ultimately applied to the entire product design process. Safety design should be considered from the initial stages of product design and should be integrated throughout the entire product development cycle. Improved safety awareness helps improve product quality, but achieving safety design does not guarantee high product quality; other factors related to product quality are beyond the scope of this article. Human-computer interaction is a process of information exchange between humans and machines. Humans are perceptual and cognitive subjects; the user's cognitive model is shown in Figure 1. Human cognitive functions are divided into four sub-functions: sensation, information processing, decision-making, and reaction, all of which rely on brain memory. Humans are complex beings, influenced by their operating environment, workload, abilities, experience, emotions, and many other factors. This makes human-computer interaction (HCI) design extremely complex. The design should aim to minimize complexity and reduce the impact of unpredictable factors, ensuring the system/device operates under predictable and safe conditions. The user panel is the HCI interface that receives user input and displays output. The key to HCI is the accurate and convenient exchange of information between humans and machines. User panel input is random, and the order or combination of operations can be diverse. User operations may be erroneous. Therefore, reducing the probability of user errors and mitigating the risks associated with misoperation are crucial considerations in the safety design of HCI systems. a) First, how to reduce the probability of user errors? Consider the fatigue caused by operator posture; otherwise, fatigue can easily lead to operational errors and slowed reactions. Operators need a comfortable posture for convenient HCI interaction. For example, bending over or using a probing device can easily cause operator fatigue. The design also needs to consider the position of operation buttons and status indicators, the tilt angle of the control panel, and whether seated operation is permissible, as seated postures are less likely to cause fatigue than standing postures. In short, it's ergonomically designed. The modular layout of the equipment's functions makes the human-machine interface more rational and logical. The layout is clear, with similar functions or those of the same safety level grouped together. A clear layout makes operation buttons easy to see and reduces the risk of error. Functionally similar buttons, such as those adjusting parameter settings, are easy to operate, and because these similar buttons are close together, accidental operation is less likely. The same principle applies to buttons of the same safety level; for example, danger switches and frequently used buttons should be separated by sufficient distance and placed in special locations. For instance, placing the emergency stop switch in a special location ensures rapid power cut-off in emergencies and prevents accidental power cut-off during normal operation. Status indicators should be clear and accurate. Indicator lights can use two colors to show normal or abnormal status, such as green for normal and a more sensitive yellow or red for warnings or abnormalities. Using indicator lights to indicate normal/abnormal status has unavoidable drawbacks—an off indicator light may indicate a damaged light source. Self-testing upon startup can improve the detectability of device failures and has a certain compensatory effect. For text-based instructions, avoid excessive text, as this can hinder timely prompts for the operator. Keep the text concise, emphasizing key words or those indicating different security levels with flashing or different colors, as color information is more sensitive than text. Furthermore, text information must consider the user's language, while graphic information avoids this issue. Industry-standard icons are particularly important for multinational products. User operation should be as simple and easy to learn as possible; it's better to have the machine run more than the user interact with it. Increased machine operation is often handled by software, and current high-speed computer technology can easily handle this. Concise user operation steps reduce the chance of errors, minimize user intervention, and lower system failure rates. Operational logic also needs to be designed, such as with interlocking or chaining button steps, reducing possible combinations of operations and avoiding meaningless actions. Interlocking prevents function B from being used when function A is being used, while chaining requires function B to be used only when function A is being used. This design ensures that user operations conform to certain standards, rejecting non-compliant operations. This reduces the combinations of user input accepted by the system and also reduces the number of test cases for product verification. (b) Secondly, strengthen the confirmation and prompts for user operations to make users aware of their operational errors. High human-computer interaction requires the system to provide corresponding responses and prompts to user operations. Different system states should be clearly displayed, using audible and visual status indicators as needed. This allows operators to know whether the current operation was successful and guides them to the next step. For example, in household appliances like sterilizers and microwave ovens, status indicator lights and audible prompts provide users with good status feedback and safety warnings. If a system error occurs, whether caused by user error or environmental factors, providing appropriate status indicators helps users correct their operations or handle the error promptly, and may even require pausing system operation. A good user interface design not only requires the system to have error detection or correction capabilities, but also ensures that users clearly understand the nature and source of the error after it occurs, enabling them to overcome the error and prevent more serious problems from arising in abnormal states. We can take the file deletion operation in Windows as an example. Deleting a file requires confirmation and first moves it to the recycle bin instead of deleting it directly. Although these operations often involve additional steps, without these safety measures, a child could easily delete useful data from the computer by randomly typing a few keys. The same applies to mobile phone panel design; deleting text messages often requires user confirmation. Additionally, some phones provide a "beep" sound when the input code is correct (when the key is set to have a sound), and a long "beep-" sound when there is an error. This allows users to clearly judge the text encoding input. Another advantage of having a sound prompt for every key input (regardless of whether the operation is correct) is that it makes it easy to detect if a key is malfunctioning. c) Finally, how to reduce the danger in the event of user error? We also need to consider how to implement safety protection measures in cases where operator error may cause harm. The points mentioned above reduce the probability of user error through design, but they cannot guarantee that users will not make mistakes. For example, if there are hazardous sources in the system during operation, requiring users to maintain a certain distance, there should be functions to prevent user contact, such as requiring the shielding cover to be closed before allowing user operation, etc. This is especially important for products with radiation sources, high voltage, or high mechanical force. For example, microwave ovens lock their doors during operation to prevent accidental opening and radiation exposure. X-ray machines automatically cut off radiation generation if the door is accidentally opened during X-ray exposure. Industrial cutting machines can be designed with controls requiring both hands to press the control buttons during the feeding and cutting process to prevent accidental injury. Another method is to reduce risk through system detection functions. For example, X-ray machines have maximum exposure time limits; even if the operator makes a serious mistake and is unaware of the problem, the system has already addressed the risk, limiting the patient's radiation exposure. Other safety measures are also available, depending on the specific application. For instance, a child lock function on the panel temporarily disables other key inputs until the child lock is deactivated, effectively reducing accidental operation in some situations. Another measure is to differentiate user levels and assign corresponding operating permissions. For example, administrators with higher professional skills have the highest operating permissions, while ordinary users can only perform simple operations. This could be achieved through password management, granting permissions by entering a password, or through hardware locks, where administrators use a dedicated key to increase their access. From the initial design stage, different types of operators should be considered. Through experimentation and investigation, various possible operating conditions and risks should be understood. Appropriate methods should then be used to avoid or reduce risks, improving product reliability and safety. Only designs that embody this principle can be considered high-quality products. Of course, the adopted solutions also need to consider product price to enhance overall product competitiveness. References: *Safety Management*, Wu Qiong and Xu Kaili (eds.), Beijing: Coal Industry Press, July 2002; *Embedded System Reliability Design*, Li Bocheng (ed.), Beijing: Electronic Industry Press, January 2006; *Reliability Engineering*, Jin Weiya and Zhang Kangda (eds.), Beijing: Chemical Industry Press, May 2005.