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.
Commonly known as a preservative in medical laboratories and mortuaries, formaldehyde is also found in other products such as chemicals, particle board, household products, glues, permanent press fabrics, paper product coatings, fiberboard and plywood.irborne concentrations of formaldehyde above 0.1ppm can cause irritation of the respiratory tract (2). Sources. Sources of formaldehyde in the home include building and insulating materials, smoking, household products, and the use of un-vented, fuel-burning appliances, like gas stoves or kerosene space heaters.