41. Over the mass grave, a tent with a special air lock has been stretched and inflated. 42. The air lock carried by Atlantis cannot be installed without Canadarm2, making its proper operation critical. 43. Bloxsom and Angelique cited the air lock device as a contributor to the improvement in outcomes. 44. The only noteworthy problem Saturday was the amount of time it took to depressurize the air lock . 45. Late Wednesday, the astronauts replaced a leaky ventilation valve at the inner entrance of the air lock . 46. The air lock adds that capability, plus more room to venture outside with big pieces of equipment. 47. Finally, they were let through an air lock guarded by massive metal doors into the reactor structure. 48. They will use the new Russian air lock for two spacewalks in October and another in November. 49. An air embolism in a large vein can also cause a dangerous air lock in the heart. 50. As soon as the air lock was bolted in place, the spacewalkers hooked up its electrical supply.
