Believe it or not, in many languages, there is only one word for safety and security, for example, in French it is 'sécurité' and in Italian it is 'sicurezza.', both of them are obviously related to the word "security".
Safe originates from Latin salvus, “uninjured, healthy. It’s associated with salus, “good health.”
Secure originates from Latin securus, “without care,” from se, “free from,” and cura, “care.”
Based on Merriam Webster Dictionary, the most important definition of safety is "the condition of being free from injury or threat," that's basically just like the main definition of security, which is "the quality or state of being free from danger." Nevertheless, there's an alternative definition for security; that's, "measures taken to safeguard against espionage or sabotage, crime, assault or escape," and that is usually the definition we're using when we refer to industrial security.
Using all these definitions, we can better comprehend the connection between security and safety. The relationship is such that increased threat, which creates a reduction in safety is created by a weakness in security. Although protection and safety are directly proportional, but are both proportional to danger. While this all may look simple, comprehending the connection between protection and safety is essential understanding the best way to incorporate the two. Surely those that own and manage industrial facilities, particularly those that many authorities have defined as critical infrastructures comprehend the significance and value of protection and safety relative to their own operations.
By definition, both “safety “ and “security” reflects the status of being free from danger, Security proposes an internal emotion, while security suggests external emotions. In some cases the two words are interchangeable, but in most cases they are not.