In the past terrorists have left bombs in bins. The bomb is much less likely to be spotted than an unattended bag and the metal bins provide extra shrapnel that injures people nearby when it detonates. For this reason there are no bins in most railway stations, most airports and many shopping centres in the world, or if they are provided they are just a bin bag hanging from a metal hoop.
For a recycling program to work, having a large, stable supply of recyclable material is crucial. Three legislative options have been used to create such a supply: mandatory recycling collection, container deposit legislation, and refuse bans. Mandatory collection laws set recycling targets for cities to aim for, usually in the form that a certain percentage of a material must be diverted from the city's waste stream by a target date. The city is then responsible for working to meet this target.
Certain public areas such as parks have litter bins which are placed alongside paths frequently walked by visitors. This encourages people to avoid littering, as littering creates an unhealthy and aesthetically unpleasant social environment.
There are some ISO standards relating to recycling such as ISO 15270:2008 for plastics waste and ISO 14001:2004 for environmental management control of recycling practice.
Recyclable materials include many kinds of glass, paper, metal, plastic, textiles, and electronics. Although similar in effect, the composting or other reuse of biodegradable waste—such as food or garden waste—is not typically considered recycling. . Materials to be recycled are either brought to a collection center or picked up from the curbside, then sorted, cleaned, and reprocessed into new materials bound for manufacturing.
In a 2007 article, Michael Munger, chairman of political science at Duke University, wrote that "if recycling is more expensive than using new materials, it can't possibly be efficient.... There is a simple test for determining whether something is a resource... or just garbage... If someone will pay you for the item, it's a resource.... But if you have to pay someone to take the item away,... then the item is garbage."