With the widespread application of modern technologies such as artificial intelligence, big data, and mobile office software in the field of human resource management, there are more and more situations such as working from home and flexible work arrangements. It is not uncommon for workers to suffer accidents and injuries during atypical working hours and in atypical workplaces. When dealing with these cases, the work-related injury determination authorities often tend not to recognize them as work-related injuries due to a lack of clear basis, and the occupational safety of workers cannot be well protected. At the same time, with the flexible development of employment methods, the number of units choosing outsourcing and other methods, as well as individuals relying on other units for operation, has gradually increased. Without establishing labor relations, it is also difficult for relevant workers to obtain work-related injury protection in the event of accidents at work. In order to better solve new problems in the recognition of work-related injury insurance and protect the legitimate rights and interests of employees and employers, the Ministry of Human Resources and Social Security recently issued the "Opinions on Several Issues Concerning the Implementation of the Work Injury Insurance Regulations (III)" (hereinafter referred to as "Opinions III"), which qualitatively describes and lists various new situations in the "Three Work Principles" regarding working hours, workplaces, and reasons for work, and grants workers the right to apply for recognition of work-related injuries under conditions such as illegal outsourcing and affiliated operations. Overall, Opinion Three conforms to the new characteristics of labor relations management in the new era, improves the rules for work-related injury identification, expands the connotation of working hours and workplace, highlights the "work reasons" more, and expands the scope of application of work-related injury insurance. It not only provides better occupational safety protection for relevant workers, but also plays a role in regulating the employment behavior of employers. Firstly, the adaptive update of the "Three Principles of Work". The traditional rules for determining work-related injuries are based on the typical labor relationship of workers on the factory assembly line. The characteristic of this labor relationship is that labor and means of production can only be combined and create value at specific times and places. Therefore, in the determination of work-related injuries, working hours, workplace, and work reasons tend to be explained and applied at the formal level. Currently, the proportion of the tertiary industry in the national economy is increasing, and employers are increasingly using modern technology to flexibly arrange work. Workers can carry out work assigned by their units anytime and anywhere. Opinion 3 defines "working hours" as "the time required by law or by the employer for employees to work," and adds "working hours specified by the employer," "time for completing temporary or specific work tasks assigned by the employer," and "overtime hours" as working hours; Define the "workplace" as "the area related to the performance of job responsibilities by employees and the reasonable area required for the performance of job responsibilities", and add "the area where the employer can effectively manage the daily production and operation activities of employees", "the relevant area outside the unit where employees are involved in completing a specific job", and "the reasonable area where employees work between multiple workplaces related to their job responsibilities" as workplaces; The definition of "work-related reasons" as "whether there is a causal relationship between the employee's performance of job duties and the injury they suffer" emphasizes the importance of job duties, and adds "injury caused by solving necessary basic physiological needs in a reasonable place during work" as a type of work-related injury. Compared with before, the work arrangement of the unit and the job responsibilities of the workers have become substantive judgment factors for work-related injuries, and the "three work principles" have been substantially expanded in both connotation and extension. Secondly, the principles for determining work-related injuries caused by working from home. Working from home is a widely used work method in recent years with the development of new technologies. In this work style, although workers balance the relationship between work and family, it also brings about the problem of difficulty in assigning responsibility for accidents caused by the difficulty in distinguishing between work time and personal time, workplace and living place. Opinion Three lists three principles for determining work-related injuries caused by working from home, namely, the arrangement of working from home by the unit, the use of modern communication methods such as WeChat for simple work communication during the period of working from home, and the exclusion of temporary and occasional situations due to work reasons. This new regulation highlights the importance of "work reasons" and installs a "safety valve" to prevent occupational risks for workers working from home. Of course, employers should also strengthen the management of working from home, limit the "working period" through online clock in and clock out, and employees should enhance their awareness of the burden of proof, retain communication records, and provide favorable evidence for reporting work-related injuries. In addition, there have been changes in the scope of application for work-related injuries. Work injury insurance is established on the basis of labor relations. Units that have the qualification of the employer as the main body outsource, subcontract, or sub contract their business to organizations or natural persons that do not have the qualification of the employer as the main body. Individuals hire personnel from other units to operate externally. This type of employment relationship cannot be recognized as a labor relationship due to the unsuitability of the main body, but these organizations or individuals who do not have the qualification of the main body of employment also carry out labor management equivalent to labor relations for workers. In the "Interpretation on the Application of Law in the Trial of Labor Dispute Cases (II)" issued by the Supreme People's Court this year, the liability for work-related injury compensation of the employing unit and the affiliated unit is determined in these situations. In line with this, Opinion Three reiterates that these situations may not involve labor relations, but the applicant for work-related injury can also file an application, which strengthens the unit's liability for work-related injury compensation and is also conducive to supervising the unit to carry out wage quality review to prevent problems before they occur. (New Press) (The author is a professor at China University of Political Science and Law and an expert in the theoretical and labor relations think tank of the All China Federation of Trade Unions)