If you stay on the line and calmly tell the operator it was an accident or test call, it is absolutely fine. I used to do telcom work for a machine shop. Part

If you stay on the line and calmly tell the operator it was an accident or test call, it is absolutely fine. I used to do telcom work for a machine shop. Part of my job was doing two 911 test calls every week (with and without an extra 9 for an outside line).