EULUMDAT is a data file format used for specification of photometric data especially intensity distributions from light sources such as lamps and luminaries. The file extension is .ldt. The format was proposed by Axel Stockmar (Light Consult Inc., Berlin) in 1990. The format is the European equivalent to the IES file format specified in IESNA LM-63. The data in an EULUMDAT file is usually measured using a goniophotometer.
Sweep or Vacuum Dirt Daily. Removing the dirt, sand or dust that is tracked in on a daily basis should be done every day. That's right, every single day. The best way to keep your hardwood floors clean and prevent damage is to sweep or vacuum them daily.
There are a lot of good products on the market you can buy to clean your hardwood floors, but grandma's time tested solution of warm water and vinegar is probably the simplest and most economical way to keep your hardwood floors clean and beautiful for years.