Handicap stencils are blue because it is an international symbol of accessibility and indicate that a parking spot is reserved for people with disabilities. The blue colour is easily recognizable and is intended to ensure that the spots are easily identifiable and distinguishable from other parking spots. This helps to ensure that people with disabilities can find suitable parking spaces when they need them. The use of blue colour for handicap stencils is standardized across many countries and is recognized as an international symbol of accessibility.

The blue colour for handicap stencils is part of an international system of signage and markings that are used to indicate accessible parking spaces, pedestrian crossings, and other facilities for people with disabilities. This system is based on the principles of universal design, which aims to make the built environment as accessible and usable as possible for people of all abilities.

In addition to the blue colour, handicap stencils often include the international symbol of accessibility, which is a stylized image of a person using a wheelchair. This symbol is meant to be easily recognizable and to convey a clear message about the purpose of the stencil.

In many countries, the use of blue handicap stencils is regulated by law and is intended to ensure that accessible parking spaces are marked and easy to find. In some cases, there may be penalties for misuse of these spaces, such as parking in a handicapped spot without a valid permit.

Overall, the blue colour of handicap stencils is an important aspect of an international system of signage and markings that helps to make the built environment more accessible and usable for people with disabilities.