SIA plane returns to Singapore due to loss of cabin pressure

[TallDutch]

SINGAPORE, Feb. 2 (Xinhua) -- A Singapore Airlines (SIA) Boeing 777-200 plane flying to the Chinese capital city of Beijing returned to the Changi Airport some 90 minutes after takeoff due to loss of cabin pressure on Saturday afternoon.

More info can be found here
http://news.xinhuanet.com/english/2008- ... 555261.htm (http://news.xinhuanet.com/english/2008-02/02/content_7555261.htm)

[PhilDernerJr]

How does a loss of cabin pressure even happen?

[NYCMedic]

Loss of cabin pressure is extremely rare, and can happen for a few reasons. A cracked window, a missing, open, or poorly sealed panel or access door on the fuselage, or a faulty relief valve could be a cause.

[HPNPilot1200]

Bad door seals are also a strong possibility. My dad has had two door seals partially fail in flight in the Citation.