Mark is cursing up a storm as he waits for the air to "leak out" of the airlock (14.2). By the way, this chapter is being told via audio recordings, rather than written logs.
Allow us to set the scene. Mark is in the airlock, even though it was launched fifty meters away from the now-deflated Hab when the fabric burst. To make things even worse, the faceplate on his astronaut helmet was broken during the impromptu launch, which gives him another leak to worry about.
Mark uses smoke to find the hole in the airlock, sealing it up with the #1 invention ever invented—duct tape. It works like a charm.
The next problem is his broken faceplate. Although Mark has a patch-kit, it won't be enough to "hold an atmosphere of pressure against" the broken faceplate (14.52). He'll need another solution.
With this, Mark turns into Space MacGyver, cutting off one of the arms of his spacesuit and gluing the fabric to his faceplate. Of course, he'll need to seal up his arm hole—plus, he won't be able to see very well—but it's better than nothing.
After accidentally gluing his hand to his faceplate like a kid making a model airplane (D'oh!), Mark seals things up as best as he can. There's still a significant leak, however, so Mark will only have four minutes to do whatever he has planned. He'll barely be able to make it to the Hab.
His one chance will be to "roll the damn airlock" closer like a hamster in a ball (14.91). Once he's close enough, he'll make a run for the Hab and grab a fresh space suit. Easy peasy?
And it works—for the most part. Mark finds the spare suit quickly, but he's unable to get it loose from underneath a table. Desperate, he grabs the helmet before high-tailing it back to the rover.
After some well-earned sleep, Mark uses another patch kit on the sliced-up spacesuit arm, giving him a perfect seal. He's still one-armed, but at least he can now stay outside to his heart's content.
The following day, he enters the Hab to assess the damage. His ration packs and potatoes are still edible, but any crops that were still growing are now dead. In other words, "potatoes are now extinct on Mars" (14.195).
Although the Hab can be repaired, there's nothing Mark can do to get those crops back. Instead of having enough food to last 800+ days, he now only has enough to last until Day 600—way before the resupply probe is set to arrive.