A first aid kit is a gathering of supplies and equipment for use in charitable first aid, and can put together for the purpose (by an individual or organization, for instance), or purchased complete. There is a wide variation in the contents of first aid kits based on the knowledge and understanding of those putting it mutually, the differing first aid requirements of the area where it may be used, and variations in legislation or regulation in a given area.
The global standard for first aid kits is that they should be recognized with the ISO graphical symbol for first aid (from ISO 7010) which is an equal white cross on a green background, although many kits do not comply with this standard, either because they are put together by an individual or they predate the principles.
The ISO only endorse the use of the green environment and white cross, and this has been adopted as standard across many countries and regions, including the entire EU. First aid kits are sometimes marked (by an individual or organisation) with a red cross on white background, but use of this symbol by anyone but the International Committee of the Red Cross (ICRC) or associated agency is illegal under the terms of the First Geneva Convention, which designates the red cross as a protected symbol in all countries signatory to it. One of the few exceptions is in North America, where despite the passing of the First Geneva convention is 1864, and its authorization in the United States in 1881, Johnson & Johnson has used the red cross as a mark on its products since 1887 and registered the symbol as a U.S. trademark for medicinal and surgical plasters in 1905.
Some first aid kits may also feature the Star of Life, usually associated with crisis medical services, but which are also used to indicate that the service using it can offer an appropriate point of care. However, for very small medical institutions and domestic purposes, the white cross on a plain, white background is preferred.
The International Organization for Standardization (ISO) sets a standard for first aid kits of being green, with a white cross, in order to make them easily recognizable to anybody requiring first aid.