Hello RecceJet,
Hope I can shed some more light on this, as I worked on the 737.
Normally, however company policy specific, are the doors "armed"
before the aircraft is going to taxi. With armed, I mean that the crew
is pulling, or switching a lever on the door. With this action, they
activate a bottle, which will cause the door to open automatically and
blow out the slide, when the large door lever is moved to open.
As the article probably suggest, did the crew not armed the doors,
which will explain the several wounded. As the doors are opened, and
the slide will not deploy, as it was not "armed".
I guess it was a B737-100/200 with the old and smoky "thunder bird"
engines, smoke from these engines is pretty "normal" on the old 737.
Hope this explains a little bit....
Regards, Ramon