Читать книгу Risk Assessment - Marvin Rausand - Страница 255

GAMAB is an acronym of the French expression globalement au moins aussi bon, which means “globally at least as good.” The principle assumes that an acceptable solution already exists and that any new development should be at least as good as the existing solutions. The expression globalement (in total) is important here because it provides room for trade‐offs. An individual aspect may therefore be worsened if it is overcompensated by an improvement elsewhere.

The GAMAB principle has been used in decision‐making related to transportation systems in France, where new systems are required to offer a total risk level that is globally as low as that of any existing equivalent system. The principle is included in the railway RAMS standard (EN 50126 1999). A recent variant of GAMAB is GAME, which rephrases the requirement to at least equivalent.

GAMAB is a technology‐based criterion, which means that it uses existing technology as the point of reference. By applying this principle, the decision‐maker is exempted from the task of formulating a risk acceptance criterion because it is already given by the present level of risk (e.g. see Johansen 2010).