To know whether the envelope that has been sent to you was opened by using steam, you just need to follow a few easy steps. First, you need to examine the flaps of the envelope, it is the place where the glue is generally present on an envelope’s body. Then you need to confirm whether the seam has a line of adhesive beyond the flap of the envelope. If you find that it is really so then it confirms the conjuncture that the envelope that has been sent to you was opened using steam.