Safety for ground testing

[dbooksta]

What safety measures can and should be taken when ground-testing fireworks?

 

There is a lot to worry about in the workshop, covered in the existing sticky topics, but assuming I have safely composed something I want to test fire I still have to worry about the following:

1. Premature ignition
2. Failure to ignite
3. Shrapnel, fire, and safety radius

My rules include the following, but I don't know if they are considered practical or sufficient for all fireworks:

• Never transport or store compounds or fireworks without adequate insulation from heat, static, and shock
• For new compositions start testing small until you can confirm safety radius.
• Avoid or protect against shrapnel: clear the test bed of debris that can be blown, and if the test device could produce shrapnel ensure all people have adequate cover for the worst possible ejection.
• Ensure nothing is flammable within the worst-case range of the device, and/or have adequate extinguisher capacity on hand for worst-case dispersal.
• Have a failsafe for failure to ignite. For me one of the scariest test conditions is a fuse that burns into a device without igniting it, or an electric match that doesn't ignite the device. I suppose there's some amount of time one can wait before calling a hangfire safe, but rather than risk approaching a smoldering firework I prefer to have a rifle on hand: Shooting a hangfired device will either set it off or else disperse it enough that I can safely approach and soak the remains.

[Seymour]

Shrapnel is easy to avoid. This, along with cost, is why fireworks are typically made of paper and clay. Assuming the clay largely becomes dust, a fragment of solid cardboard is not a great risk if the proper personal protective equipment is worn, or appropriate safety distances are used.

 

Especially considering that you seem to be making "fireworks" that just make a bang, there is a lesson to be learned in hanging ground salutes on a bit of string from a frame or tree branch. While a salute can be made that produces no dangerous debris, placing it directly on the ground can turn nearby objects such as stones in to shrapnel.

 

I guess good fuse is key for avoiding premature ignition and failure to light. If used properly, failure rates should be pretty close to nil, and you should have plenty of time to walk to a good distance as the fuse burns.

 

Fire risk is of course very varied depending on the place and climate at the time. Ultimately there are times that I just give lighting stuff a rest because of dry vegetation, and wait a few months for rain to come. It's not worth the risk. But you can still spend the time making really elaborate and time consuming shells

Edited December 16, 2013 by Seymour

[Arthur]

Fire tests at a good place and fire them electrically. 100m of twin wire costs less than a trip to the hospital.

[HissingRDX]

In blasting, usually 30 minutes is allowed before approaching a failed charge.

[nater]

 

 

Shooting a hangfired device will either set it off or else disperse it enough that I can safely approach and soak the remains.

 

hmm. This is bad safety advice, on many levels.

 

There's nothing wrong with waiting 30 minutes for a hangfire and soaking the device. Just remember that soaking the outside does not usually render the inside inert.

[Mumbles]

That is true of plastic for sure. With paper, it should eventually soak to the core assuming normal glues were used. At the very least, it will allow you to safely and easily unwrap the pasting and spiking to allow water to the core.

[Arthur]

As one or two on here can attest pyro is a risk hobby. Every time you need to minimise the risks, minimise the hazards, and use some chosen PPE to keep you safe. BUT still sometimes it will come back to bite you.

[nater]

... With paper, it should eventually soak to the core assuming normal glues were used. At the very least, it will allow you to safely and easily unwrap the pasting and spiking to allow water to the core.

 

I've never tried to open up a plastic shell, but I have soaked and opened up commercial paper shells and found the burst and stars to be dry. It was much easier to unwrap the pasted paper. Most shells I have had to dispose of have been commercial Chinese ball shells that failed during shows. I did have an Excalibur clone consumer shell that was repaired and failed twice before I soaked it to dispose of it. It sat in a bucket of water for a week and still had dry flash and stars on the inside Those shells are not built how we typically build a cylinder shell, which might have a lot do with it being harder to dispose of.

 

I have not taken apart any hobbyist made shell that I didn't make for fear of not knowing what was inside or how they were made. I always feel like it is safer to make every attempt to fire a shell as it was intended rather than disassemble it. I certainly wouldn't shoot a dud shell, but I assume the OP only makes salutes.

[dbooksta]

hmm. This is bad safety advice, on many levels.

 

Please elaborate. Safety is paramount! (But remember I'm talking about ground test range safety: components we want to test on the ground, not components mounted in a mortar or on a lifting charge, where presumably there's some emergency fire control system in place to soak the base charge if there's a ground failure.)

[nater]

While I am not opposed to shooting, nor am I opposed to exploding targets, shooting duds to dispose of them is a ridiculous idea. A rifle round isn't not guaranteed to set off a pyro device. You're just adding another element of risk while attempting to dispose of a dud. It is obvious to me that you're making ground bombs. If you can't make them ignite reliably using a fuse, then you have no business making them at all.