Sustained stress refers to a constant, ongoing pressure or force acting on a system or an organism over an extended period. This differs from occasional or transient stress, which occurs intermittently.
Sustained Stress in Engineering:
In engineering contexts, especially piping systems, sustained stress refers to the stresses present throughout the operating cycle of a system. These stresses result primarily from weight (pipe weight, insulation weight, fluid weight, etc.) and pressure (internal and external). It is crucial to keep sustained stress below allowable values to ensure the structural integrity and longevity of the system. ASME B31.1 and B31.3 codes are relevant standards providing guidance on allowable stresses for sustained loads in piping systems. Software like Autopipe is used to calculate sustained stress, often considering corroded wall thickness for a conservative approach. (References: Universal Engineering Consultants, Eng-Tips, What Is Piping, Little Peng, Hexagon PPM)
- Examples: The constant weight of a pipeline filled with fluid and the continuous internal pressure exerted on the pipe walls contribute to sustained stress.
Sustained Stress in Biology and Psychology:
In the context of biology and psychology, sustained stress refers to prolonged exposure to stressors. This constant activation of the stress response system (e.g., release of cortisol) can disrupt various bodily processes, increasing the risk of numerous health problems. Sustained stress impacts physiological functions and mental well-being, influencing performance and potentially leading to chronic health issues. (References: Mayo Clinic, PubMed 9035259, PubMed 18199969, PubMed 32600739, Cedars-Sinai)
- Examples: Chronic job stress, ongoing financial worries, or persistent relationship problems constitute sustained stress impacting an individual's physical and mental health.
