I've never seen a 40 ng/ml cutoff. The most common is 50 and then there is 20 and 100. There is a chance you may be subject to the 20 ng/ml being i nthe mental health field. Try to look back on your chain of custody form and see if you see something like SAP 10/50 w/nit or similar numbers and post them. If it was the 50 ng/ml cutoff and you passed a home test with the first void of the day you stand an excellent chance of passing. With your stats I also like your chances.