Are there special considerations while inserting the flash bulb? FAQ Report The bulb should be inserted according to the directions in the user's manual, only after making certain that the instrument has been disconnected from the wall outlet. Avoid touching the bulb with your hands, use gloves or a tissue to insert the bulb. After the bulb has been inserted make certain that the outlet flap does not contact the bulb when it is being rotated up and down. Contact with the bulb could cause damage or breakage.