Welcome to the 4th International Symposium on Environment, Health and Safety (ISEHS), which successfully took palce on October 17-18, 2024, in Debrecen, Hungary. ISEHS 2024 aimed to provide a platform for experts from all three pillars of EHS to share their latest research contributions and exchange knowledge, with the common goal of creating a cleaner, healthier, and safer future. More than 115 participants from eight countries registered for the 2024 event. The scientific program included 23 lectures covering a wide range of topics, including but not limited to: environmental protection and management (water and wastewater treatment, soil remediation, greywater utilization); occupational safety, fire protection, and industrial safety; protection against ionizing radiation and nuclear safety; energy storage.