Reference articles on history, science, culture and more
Surprise meSurprise meSubscribe
Encyclopedia

Reliability, availability, maintainability and safety

Engineering characterization of a product or system

Wikipedia contributorsAdapted for Fathomly · View authors
1 min read
Source updated September 3, 2025

In engineering, reliability, availability, maintainability and safety (RAMS) is used to characterize a product or system:

  • Reliability: Ability to perform a specific function and may be given as design reliability or operational reliability
  • Availability: Ability to keep a functioning state in the given environment
  • Maintainability: Ability to be timely and easily maintained (including servicing, inspection and check, repair and/or modification)
  • Safety: Ability not to harm people, the environment, or any assets during a whole life cycle.
Watch videos about Reliability, availability, maintainability and safetyExplainers and documentaries on YouTube (opens in a new tab)

Sources and credits

This article is adapted from the Wikipedia article “Reliability, availability, maintainability and safety”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

Fathomly is not affiliated with or endorsed by the Wikimedia Foundation. Spotted a problem? Tell us.

Continue exploring

Related topics

Systems engineering

Systems engineering is an interdisciplinary field of engineering and engineering management that focuses on how to design, integrate, and manage complex systems over their life cycles. At its core, systems engineering utilizes systems thinking principles to organize the systems engineering body of knowledge.

Dependability

In systems engineering, dependability is a measure of a system's availability, reliability, maintainability, and in some cases, other characteristics such as durability, safety and security. In real-time computing, dependability is the ability to provide services that can be trusted within a time-period.

Failure cause

Failure causes are defects in design, process, quality, or part application, which are the underlying cause of a failure or which initiate a process which leads to failure. Where failure depends on the user of the product or process, then human error must be considered.