Typically made in a "blown-film extruder," certified compostable bags are used in a variety of applications. Large-capacity bags are used in municipal leaf and yard waste collection programs. Smaller-capacity bags are used for residential or commercial collection of food waste. Certificed compostable bags have the advantage of keeping collection bins dry and free from odors. This increases collection participation rates. Clear- or lightly tinted bags have the added advantage of allowing collection workers to spot contaminants inside the bag, preventing non-biodegradable items from being collected with other organics.