Flammability limit

So you gotta have a, a good balance of, um, the ox-- safe oxygen range in a confined space.

What should the lower or the LEL or the LFL be below for a confined space entry? And that is ten percent.

So, um, so it's like, I think it's the lower, um I forgot the name of it that quick.

I'm so sorry.

But, um, it's the LEL and the LFL, and it's ten percent, um, be below for confined space entry.

Um, next, what breathing equipment can be used in confined spaces? And the breathing equipment that's used in confined spaces is SCBA, or self-contained breathing apparatus.

Um, we definitely use those in confined spaces and for spaces that have, um, hazards of any types of, uh, gases or anything like that, you need to have a, a proper SCBA.

... commonly used instrument in the fire service.

You have oxygen, LEL, combus- uh, carbon monoxide, hydrogen sulfide.

You have four numbers.

Looks simple, right?

Your meter reads 20.9 oxygen-

Okay

... zero LEL-

Mm-hmm

How do responders accurately assess those hazards while operating on scene? And how should air monitoring be incorporated into these incidents?

For first responders, I think a critical piece is a five gas meter with LEL capabilities, because the likelihood of knowing in advance of the chemistries of the batteries that you're dealing with as a first responder is pretty low.

You're just probably not going to know that.

So it's better to be prepared for the worst case scenario, irrespective of the chemistry.

We see smoke, flames, we feel heat, yada, yada, yada.

Um, now hazmat gives you, oh, 10 parts per million, 2.4% LEL, a PID reading, a pH of one, a detection tube, blah, blah, blah, and then all of a sudden the confidence level drops.

Why is that?

Mm-hmm.

Mm-hmm

... is s- still at 20.9.

Your LEL s- still says zero.

What does that tell you? And suddenly...