U.S.-based National Fire Protection Association standard fire diamond for flagging risks posed by hazardous materials. The red diamond has a number 0-4 depending on flammability. The blue diamond has a number 0-4 depending on health hazard. The yellow has a number 0-4 depending on reactivity. the white square has a special notice, e.g OX for oxidizer.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Here's a camo print with more tan and less green, such as might be used in a desert scenario. This is tileable, so it can be used as a wallpaper or background.
Source Eady
From a drawing in 'Hundert Jahre in Wort und Bild', S. Stefan, 1899.
Source Firkin
A cute x, if you need that sort of thing.
Source Juan Scrocchi
The starting point for this was a texture drawn with the 'Radial Colors' plug-in in Paint.net.
Source Firkin
Prismatic Curved Diamond Pattern 6 No Background
Source GDJ
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
A repeating gloomy background image. This one consists of a pattern of black chains layered on top of a dark textured background.
Source V. Hartikainen
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
This metal background pattern resembles a metal plate with rivets. Solid rivets on a metal plate.
Source V. Hartikainen
Sort of like the back of a wooden board. Light, subtle, and stylish, just the way we like it!
Source Nikolalek
A playful triangle pattern with different shades of gray.
Source Dimitrie Hoekstra