Definition. A metric space is a set X together with a function d (called a metric or distance function) which assigns a real number d (x, y) to every pair x, y X satisfying the properties (or axioms): 1  d (x, y) 0 and d (x, y) = 0 x = y, 2  d (x, y) = d (y, x),
Here are some facts and guidelines about formaldehyde in plywood and OSB that can help you when building a chicken coop: 1  Formaldehyde is used in the binders and resins of some manufactured wood products. 2  Offgassing can be an issue with products containing urea-formaldehyde (UF) resins.
It is used in pressed-wood products, such as particleboard, plywood, and fiberboard; glues and adhesives; permanent-press fabrics; paper product coatings; and certain insulation materials. It is also used to make other chemicals. Formaldehyde is quickly broken down in the air â generally within hours.ometimes, although formaldehyde is not used, substances that release formaldehyde are. These have been found in cosmetics, soaps, shampoos, lotions and sunscreens, and cleaning products. Formaldehyde can be added as a preservative to food, but it can also be produced as the result of cooking and smoking.