My Delmhorst j-lite meter arrived today and I have a question on taking readings. The manual says stick the pins in parallel to the grain. In Oak strip flooring to me that means stick it in the end of the board, not the back or face. Is that correct? Also, when I measure my OSB subfloor, I can't really stick it in the side. I'm just sticking straight into the floor. If I'm measuring the right spots, I seem to be good to go. My humidity level in the house is running 40% to 45% percent at 69F. The floor measures between 7% and 10% MC as does the new oak flooring which have been acclimating for a while. The meter has an enclosed table for different wood types. It doesn't show an OSB conversion. Should I just use the actual reading? The table does show red oak as using the actual reading with various other conversions for different wood.

The probes should go into the face of the flooring. With the probes inline with the grain of the wood. With OSB since it is a composite material measuring moisture levels can be less than perfect.

You might be able to obtain specific gravity specifications from the manufacturer of the substrate if it is known, or you could use a general specific gravity of 0.75 which should suffice.

Thanks for clearing that up. I see after your explanation what they mean by parallel with the grain. Is it all right to use the back of the board instead of th face. I hate to mees up the face.

NOT a problem.