Once an electric pressure cooker reaches pressure, you cannot open the lid until the pressure is back to normal. There are two ways to do this - a quick release, where you are forcing the excess steam and pressure to be released and natural release. Natural release allows the pot to slowly cool down and lose pressure. This can take anywhere from 5-40 minutes depending on what you are cooking. (The hard boiled eggs will take 5-10 minutes.) Natural release is part of the cooking process.