Muffler (silver) and exhaust pipe on a Ducati 695 motorcycle. A muffler (silencer in English) is a device for reducing the amount of noise emitted by the exhaust of an internal combustion engine.
Quick Answer. Normal blood sugar levels should be  less than 100 mg/dL when fasting and less than 140 mg/dL two hours after eating, according to WebMD. People without diabetes tend to have blood sugar levels of around 60 to 90 mg/dL before eating.
If an individual's sustained blood sugar falls below 55 milligrams per deciliter (mg/dL) or measures higher than 180mg/dL, he is considered to have dangerous blood sugar levels. Normal blood sugar levels typically range from 82 to 110mg/dL, but these tend to fluctuate when an individual eats or forgets to eat.