Especially understanding that different types of wood soak in stain differently, and even though you are using the same exact method you get a completely different outcome. (roomsforrentblog.com)
On - site examination would be necessary to clarify exact methods. (en.wikipedia.org)
What the researchers do agree on is the need to keep defining the toxicity of each of these harmful substances, studying their effects on health and developing more and more exact methods of analysis. (sciencedaily.com)