A method of connecting or disconnecting a first tubular to a second tubular includes engaging the first tubular with a power tong; engaging the second tubular with a backup tong; and rotating the first tubular relative to the second tubular. The method also includes, while rotating, monitoring a distance between the backup tong and the power tong and comparing the distance to a first threshold value; and stopping rotation of the first tubular when the distance equals to the first threshold value. According to one embodiment, a tong assembly includes a power tong, a backup tong, a sensor configured to measure a distance between the power tong and the backup tong, and a controller configured to compare the distance to a threshold value.