[Cletus.D.Yokel]

A case of media pornography.

Sprinklers are used by the landscaping industry. That industry also uses nitrates for fertilizer. The same chemical family of nitrates used in C4 (McVeigh used nitrate fertilzer as did the rags that blew up the WTC garage in 1993).

The test came back positive for nitrates, some "journalist" asked what that meant and the Port Authority representative says, "it can be used in explosives like C4."

Voila! C4 is much more "pornographic" than "fertilizer".

[El Gato]

C4 is a good long ways from Harmonium Nitrate, or even Bat Guano. These sprinklers were for the fire suppression system, and thus would not have been in the landscaping industry. (And even if the two sorts of sprinklers were made in the same factory, they wouldn't get exposed to nitrates there)

The explosive ingredient in C4 is RDX

This is ammonium nitrate:

As you can see they aren't at all similiar, other than both containing nitrogen, hydrogen, and oxygen.

[streetpreacher]

It sounds irresponsible when even stated that way as if the port rep wants to scare the journalist with the info.

Wanna' be J. Edgar Hoover feeds info to wanna' be Edward R. Murrow.

But it probably happened just as you stated.