I was typing an e-mail to my co-workers at 02138 yesterday, working on the 13th floor in our offices at 110 E. 42nd Street, when suddenly there was an incredible rumbling, a sound more enormous and three-dimensional than anything I’d ever heard—like an avalanche of grinding, booming noise chewing up the air.

I stepped out of my office and said, “What is that?” A colleague in the next room said, “Something happened to the building across the street—everybody get out!” The view outside his window was dust and ash and smoke. The rumbling hadn’t stopped.

Get out we did. I grabbed my keys, wallet and cell phone, and then dashed for the stairs. Everyone else in the building was having the same thought; I didn’t see anyone waiting for the elevators.

As I sprinted down the stairs, a woman behind me was screaming. “I don’t want to die today! I don’t want to die today!” I heard her as I made my way down. Possibly I should have stopped to calm her down; I didn’t even think of it. I had no interest in dying that day either.

When I got to the bottom of the stairs, three men in ties sprinted past me going the opposite direction. “That’s up!” I shouted to them. They turned around and we headed for the back door, but whatever had happened had happened right outside it, and we turned and made our way to the front entrance onto 42nd Street, directly across from Grand Central. I have never in my life been so conscious of the weight of a building overhead, the feeling of being underneath something that weighs tons and tons and, for all you know, is about to start collapsing onto you.

Thousands of people were already outside. People were screaming and running. A man in front of me was being helped by someone else; the backs of his legs were covered with blood. They looked like they had been peeled. I tried to take some pictures from my cell phone, but every time I stopped I almost got trampled. I didn’t notice till later that my clothes were covered with dust and mud.

There wasn’t a person there who didn’t believe that a bomb had gone off, myself included. I was convinced that the building opposite ours had been blown up, and for the next fifteen minutes to half an hour, I walked in the belief that hundreds of people who worked right next door to me were now dead, and that I was a survivor of a terrorist attack. All the shades of 9/11 were present: the wall of sound, the crowds running through the streets, the air filled with sirens, the businesspeople covered with dust, the inability to make a cell call because “all circuits are busy now.”

Who do you call when you think you’ve just survived? Who don’t you call?

Now I know, not just in theory, and it is a profound knowledge.

I talked to two people on the street who thought that their building had been blown up—101 Park Avenue was the address. “What’s in it?” I asked. Offices, one said. “Why would anyone want to blow it up?” (As if there could ever be a logic to such an act.) The man just shrugged, and suddenly I felt terrible, asking him these questions when he believed that his co-workers were dead. Because we no longer think that people in buildings that are attacked live; we assume that they are dead.

In the end, it was all because of a pipe. A frigging pipe.

An enormous sense of relief, of course. But I also feel an incredible anger at the city and at Con Edison, whose pipe it was. You fuckers—why didn’t you tell us? Why didn’t you tell us that pipes can explode like that, and shower debris 20 stories high and make a sound like you’ve never heard and never want to hear, a sound like you imagine the sound of a building crumpling to the ground would make?

Would it have made a difference? I don’t know; probably not.

All I know is that I now know what it feels like to believe, even if only for a short while, that one has survived a terrorist attack, and that hundreds of people who share a street with you did not. And I know how close 9/11 is to the surface of all of us who lived through that day in Manhattan, like a bomb, planted under our skin, just waiting to go off.