Risk plus barriers = safety?

According to a common safety model, safety can be brought about either by eliminating hazards, by preventing initiating events, and/or by protecting against outcomes. The two primary types of responses, prevention and protection, both involve the use of barriers in one way or another. The paper discusses the characteristics of different barrier systems (physical, functional, symbolic, and incorporeal) and their relative advantages and disadvantages. It is argued that while barriers are necessary, they basically represent a reactive approach which is insufficient by itself to guarantee safety. (c) 2007 Elsevier Ltd. All rights reserved.