Construction safety is important in the domains of architecture, engineering and construction. However, studies have rarely discussed safety issues from the perspectives of employers or employees' ignorance of safety requirements. A novel approach with modeling and reasoning functionalities is applied for semi-automated identification of safety requirements from construction safety standards. The proposed approach is based on ontological modeling and document modeling techniques. These techniques model safety concepts and requirements in semantically-rich, human-readable and computer-interpretable format. These features further enable reasoning about the concepts and requirements needed to identify applicable safety requirements. Test cases are used to validate the approach and illustrate its advantages. Validation results are discussed, and conclusions and directions for future research are given. The proposed approach can benefit construction safety by improving participants' awareness of safety requirements.indicated that safety regulations that mandate the use of preventive measures can help prevent many accidents. Therefore, complying with construction safety requirements can be regarded as a fundamental practice that promotes construction safety. However, retrospective or proactive safety-related studies seldom emphasize the significance of safety regulations or discuss how to identify applicable safety requirements.Additionally, Laurence (2005) claimed that when safety requirements are not identified, project participants may be unaware of safe behaviors, resulting in occupational hazards and possibly leading to fatalities, injuries, and illnesses.However, many sources of information about safety requirements exist, such as the federal government, state and city governments, the employer's own company, and trade associations (Brauer 1990). As different sources provide different safety requirements, identifying the safety requirements which are applicable to an activity is both cumbersome and time-consuming, and careful review and identification of applicable safety requirements may be hindered many safety requirement sources.Although some safety databases are available, such as the Canadian enviroOSH Legislation plus Standards (Canadian Centre for Occupational Health and Safety 2013), and allow for keyword-based searches for safety requirements, simply using keywords to search for applicable requirements is ineffective. Keyword-based searches are often too general or too specific, such that documents which are not of