This paper aims to present solutions based on inherently safer design (ISD) principles to reduce the risks related to interventions in confined spaces and discuss their general applicability in a design situation or installations retrofit by exploring the client-designer relationship. A literature review on ISD solutions for confined spaces was followed by semi-structured interviews with 15 experts on confined space risk management in Quebec, Canada. The solutions based on the literature were confronted with experts' knowledge on the real-life conditions in confined space interventions. Our findings suggest that considering the entire confined space's life cycle in design is still very marginal (e.g., questioning the necessity to enter). As designers tend to replicate non intrinsically safe designs (e.g., inadequate entrances dimensions), end-users will then require retrofitting the structures over time, which usually costs more in the long term than implementing ISD solutions earlier. The notion of declassification of the confined space to eliminate confined spaces can give a false sense of safety. Its contribution to accident prevention depends on how end-users reduce inherent or task-induced risks as low as reasonably practicable. This paper categorized declassification into three types: total elimination, hazard-oriented declassification, and organizational declassification. Since the implementation guidelines of these risk reduction strategies are absent in the literature, this paper provides a risk reduction model that shows how end-users can identify application phases, declassify a confined space, and manage residual risks at the design phase in real-life environments.

本文旨在提出基于固有安全设计 (ISD) 原则的解决方案，以降低与密闭空间干预相关的风险，并通过探索客户与设计师的关系讨论它们在设计情况或安装改造中的普遍适用性。在对密闭空间 ISD 解决方案的文献回顾之后，对加拿大魁北克的 15 位密闭空间风险管理专家进行了半结构化访谈。基于文献的解决方案与专家对密闭空间干预中现实生活条件的了解相结合。我们的研究结果表明，在设计中考虑整个密闭空间的生命周期仍然非常微不足道（例如，质疑进入的必要性）。由于设计师倾向于复制非本质安全设计（例如，入口尺寸不足），随着时间的推移，最终用户将需要对结构进行改造，从长远来看，这通常比早期实施 ISD 解决方案的成本更高。将密闭空间解密以消除密闭空间的概念可能会给人一种虚假的安全感。它对事故预防的贡献取决于最终用户如何将固有的或由任务引起的风险降低到合理可行的最低水平。本文将解密分为三种类型：完全消除、面向危害的解密和组织解密。由于文献中没有这些风险降低策略的实施指南，本文提供了一个风险降低模型，展示了最终用户如何在现实生活中的设计阶段识别应用阶段、解密密闭空间和管理剩余风险环境。