There’s red, there’s white, and it even comes in English, Chinese, Malay and Tamil. All this in a rectangular board about the size of a flag. The “Danger-Keep Out!”sign is how I remember my Singapore, a ‘flag’representing the visual culture that surrounds us in this city. You can find it all around in this city, which is perpetually in construction or undergoing some makeover. As long as something is being built, serviced, or torn down, this simply designed sign helps to keep Singaporeans safe by communicating to us that there’s dangerous work going on behind it, and we should keep…