A blowout preventer (BOP) (pronounced B-O-P) is a specialized or similar mechanical device, used to seal, control and monitor and gas wells to prevent , the uncontrolled release of crude oil or natural gas from a well. They are usually installed in stacks of other valves. The earliest blowout preventers; Regan Type K Annulars were used, beginnin.
[pdf] 
An oil rig blowout occurs when uncontrolled pressure builds up in the wellbore, causing a sudden and forceful release of oil, gas, or drilling fluids from the well. Blowouts can result in fires, explosions, and the release of toxic gases, making them extremely dangerous to the workers on the rig and the. .
A kick is a precursor event to an oil rig blowout. It is an influx of formation fluids, such as oil or gas, into the wellbore, which often occurs when the downhole pressure exceeds the. .
The primary cause of an oil well blowout is the failure to maintain control over the pressure within the wellbore. This can occur due to various reasons, such as: .
Gushers were an icon of during the late 19th and early 20th centuries. During that era, the simple drilling techniques, such as , and the lack of meant that drillers could not control high-pressure reservoirs. When these high-pressure zones were breached, the oil or natural gas would travel up the well at a high rate, forcing out the drill string and creating a gusher. A well which began as a gusher was said to have "blown in": for in.
[pdf]