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.
Avoid the use of foamed-in-place insulation containing formaldehyde. Use panel products not made with urea-formaldehyde glues. Use particleboard panel products conforming to ANSI A208.1-1993. Ensure cabinets made with particleboard contain a high percentage of panel surface and edges that are laminated or coated.isk. Formaldehyde is normally present at levels less than 0.03 parts per million (ppm) in both outdoor and indoor air. Rural areas have lower concentrations than urban areas. Indoor levels can increase with the presence of products that may add formaldehyde to the air.