How Unqualified Individuals Are Affecting DHAs

Jason’s first appearance on the podcast was back in Episode #12, when he talked about qualified persons and combustible dust hazard training. He has been doing dust hazard analyses (DHAs) ever since the term was created by NFPA 652. He is also a former OSHA Compliance Officer who has cited over a hundred general duty clause citations.

“I also sit on a lot of the NFPA committees to help write these standards- I’m the Chair of the Wood Dust Committee NFPA 664,” he says.

What Challenges Are Out There with ‘Qualifications’ Related to Combustible Dust?

“More and more people are doing DHAs that I’ve seen. I’m not saying that’s a bad thing, but (a lot of) the people who I see doing them aren’t qualified to do them,” Jason says. “In my opinion and in my opinion alone, this is where NFPA has failed. And I have to take responsibility for that because I sit on the 652 committee. This is where we failed.”

In Jason’s opinion, the definition for a qualified person is too vague and needs to be redone.

“It’s basically a performance-based type of thing when it should be more prescriptive in my opinion. But what I’m seeing is, especially a lot of safety health consultants right now and some engineering firms, are doing DHAs. But then when you go to research some of these people, even on their websites, they don’t even mention combustible dust on their websites. But yet they’re doing DHAs and their experience is little to none.”

He explained that having an unqualified person do your DHA, the report will not be as specific as it should and one of two things will happen.

  • Hazards are going to be missed.
  • You’re going to get a control in terms of a recommendation. It’s going to tell you to implement a control when you may not need it – which is going to lead to thousands of dollars and possibly hundreds of thousands of dollars in unnecessary costs.

Properly-done DHAs will have several recommendations and differentiate which ones need to be done now instead of later.

“If you don’t have some way to differentiate what you should do now and what you should do later, you’re going to be overwhelmed,” Jason says. “And then typically what happens at that point is people just throwing it in their filing cabinet and say “Yeah, we’re done with it now” and it ends up in the black hole until, God forbid, an incident happens or an AHJ – Authority Having Jurisdiction –  shows up and asks for it and ask why you didn’t do anything with it.”

He advised anyone using a consulting firm or other external entity to confirm their qualifications and not let price be the guiding factor.

How Have Unqualified People Impacted DHAs in General? 

Jason answered this question by using real-life examples.

The first company was doing metal surface removal, so it generated metal dust inside of an enclosed booth where an employee worked. The dust being generated went into an exterior dust collector with explosion protection and isolation. Vents were correct in terms of sizing, discharge or location.

“So everything looked good on the report, but the client asked me, “What do you think?” They had me review this and I’m looking through it again, the DHA. They did a decent job on everything they needed to with dust collection and everything like that. But they made a recommendation to put a deflagration vent on the booth.

“Now, I’m not disagreeing with that because I do think it’s above the minimum explosible concentration. Where that problem comes into effect is they apparently forgot that there’s an employee inside this booth. So putting a deflagration vent on the booth doesn’t do anything for them. You’re going to kill them. If there’s actually a deflagration in there, they’re in there with it, they’re dead at that point.

“When I brought that to the attention of the client, I don’t think they saw it either until I brought it up. Okay, well, yeah, no one ever thought of that poor employee in there. So that’s one of the first examples there that I think some people get focused too much on, you know, “Okay, we have some problems, let’s fix it.” But you have, you don’t seem to see the employee or the kind of employee exposure there, that simply protecting that equipment is not going to do anything for this employee.”

The second example involved 3D printing.

“I see all kinds of DHA reports for 3D printing that don’t cover the printers because the people assume they’re done correctly. And I can honestly tell you they are not,” Jason says. “Some of the printers out there are not designed correctly and you ignore serious hazards like condensate that can spontaneously combust and lead to flash fires that have caused several second or third-degree burns to employees. On at least 90 percent of the reports I’ve seen, condensates aren’t even covered in the DHA.”

He added that people also overlook 3D printing filter changes, which involve powder transfer and extraction in non-inert atmospheres.

A third issue is DHA consultants simply regurgitating NFPA and OSHA standards.

I saw one (report) here where they recommended to put deflagration venting on this dust collector. It was indoors. They just left it at that. They said put deflagration venting. Well, that right there tells me you’re not qualified because you just told them to have a big fireball in their facility. You never told them to duct the outside, to discharge stuff through a flame arrestor or something, to make sure that you don’t have that fireball coming through.”

Jason pointed out that this report didn’t research performance-based design options.

“There were only two sources of ignition for this dust collector: essentially static and tramp metal. And if you can control those two sources of ignition, you don’t need to put explosion protection on the dust collector because you have nothing to ignite it… I can tell that if you don’t examine performance-based design options, you’re not getting the full benefit of that DHA.”


Jason emphasized that not all DHAs are created equal.

“There are a few prescriptive requirements if you look at NFPA standards for DHAs. But honestly, they’re all performance-based. I don’t necessarily have a problem with that. It keeps it open and I get that. But because of that, if you’re going to do a DHA, you’ve got to do your research primarily on that qualified person because it’s all going to come back to him or her or the team or whoever it is of how good that DHA is going to be. It is all on that person, whoever it is.

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