Risk Advice Thread

[buzzbomb]

Does this look better?
View attachment 231863

Definitely missing one. The majority of the planes that I have built, have a drop or two of my blood on them. I seem to have a hard time building a plane without nicking my thumb with a razorblade, somewhere in the process. The mitigation on that would be to pay attention to where the heck your blade and thumb are in respect to each other.

Prop activation is very likely without mitigation. The mitigation is to have the motor turned off when the battery is connected, and very much preferably, do that AND have a throttle shut off switch. A propeller protector won't necessarily protect the person. It's meant to protect the propeller in a crash.

"LiPo Battery Fires" is tough. One hopes everyone follows the recommended steps to avoid one, and if they do, there isn't likely to be one. People still die from carbon monoxide poisoning everyday, because they didn't follow the basic safety guidelines for say, a generator. That's a hard one to quantify.

Electrocution is a likelihood of "Z." I mean, it's possible, but that dot is way out at the corner of the chart.

The likelihood of human collision shouldn't be an "A." It is fully within the realm of possibility that someone could fly an RC aircraft into another person, but it is certainly very, very rare.

If it were to happen, it could be bad. Anything where you're charting the possible risk of that spinning blade hitting unprotected flesh? The blade wins. If your "Risk Level" is how much you can get hurt? Yeah, that's pretty high.

I would change "Hot Glue burns" to an "A." Not a question of "if" only "when." Also, it's not a chemical burn. It's due to the heat of the glue and the fact that we hold things together and pretty much ignore the obvious pain. The worse burns I've ever had from hot glue were simply a blister (simple pain does win out over obstinance, pretty quickly and you've got to move your hand.)

Don't know if I helped or muddied the waters, but there's my 2c.

 

[danskis]

If you included flying an RC plane in the assessment you would have additional risks (if you want to expand your table)

 

[NathanSchool]

Definitely missing one. The majority of the planes that I have built, have a drop or two of my blood on them. I seem to have a hard time building a plane without nicking my thumb with a razorblade, somewhere in the process. The mitigation on that would be to pay attention to where the heck your blade and thumb are in respect to each other.

Prop activation is very likely without mitigation. The mitigation is to have the motor turned off when the battery is connected, and very much preferably, do that AND have a throttle shut off switch. A propeller protector won't necessarily protect the person. It's meant to protect the propeller in a crash.

"LiPo Battery Fires" is tough. One hopes everyone follows the recommended steps to avoid one, and if they do, there isn't likely to be one. People still die from carbon monoxide poisoning everyday, because they didn't follow the basic safety guidelines for say, a generator. That's a hard one to quantify.

Electrocution is a likelihood of "Z." I mean, it's possible, but that dot is way out at the corner of the chart.

The likelihood of human collision shouldn't be an "A." It is fully within the realm of possibility that someone could fly an RC aircraft into another person, but it is certainly very, very rare.

If it were to happen, it could be bad. Anything where you're charting the possible risk of that spinning blade hitting unprotected flesh? The blade wins. If your "Risk Level" is how much you can get hurt? Yeah, that's pretty high.

I would change "Hot Glue burns" to an "A." Not a question of "if" only "when." Also, it's not a chemical burn. It's due to the heat of the glue and the fact that we hold things together and pretty much ignore the obvious pain. The worse burns I've ever had from hot glue were simply a blister (simple pain does win out over obstinance, pretty quickly and you've got to move your hand.)

Don't know if I helped or muddied the waters, but there's my 2c.

Here are my changes:

Can you explain how cuts can be a risk for 3d printed airframes?

 

[NathanSchool]

Here are my changes:
View attachment 231879
Can you explain how cuts can be a risk for 3d printed airframes?

Is there anything else I should add?

 

[hankflies03]

Is there anything else I should add?

I would just add razor blade cuts as maybe a likelihood of A and risk level 3
move lipo fires down to a C or D and change prop activation up to a B or C

 

[mastermalpass]

It's coming along nicely. A tip I would give on the kind of risks you're writing up is to go back a step.

So for example, you have (and I know I suggested this at first) Accidental prop activation as the risk and protection & first aid for mitigation of injury or damage caused.

As well as mitigating the damage, let's also mitigate the most likely cause; the throttle got pushed. So a few times I've accidentally caught the throttle with my sleeve or I've moved something into it, or it's fallen over onto the throttle, or something fell on it. Since going through all that I've learned:

Risk: Unintended throttle input.
Description: Unintended throttle input causing prop to spool up when user is unprepared, risking damage to objects and injury (lacerations, bruising).
Response: Avoid
Avoidance measure (mitigation): Keep throttle stick clear of clothing, ensure firm grip of transmitter. Place transmitter down on secure surfaces clear of anything that can move. Only power on model when necessary.

Now we can write up a separate risk, for the prop spooling up by other means:

Risk: Unintended motor actuation
Descripton: motor spools up without throttle input. If prop is attached it can cause damage and injury.
Response: Mitigate
Mitigation: Test the motor without the prop attached to ensure ESC and transmitter function correctly. Test throttle input to check the that ESC is calibrated and that the motor responds to throttle correctly.

I find when you break things down like this, it's easier to figure out what you have to do to mitigate, avoid or accept risks. For example when it comes to crashing, that's a risk we accept - it's a lot of work to ensure 95% that a plane doesn't crash, wouldn't be fun, so we just crash. 😂 But a plane crashing into people well, we can't mitigate injury with bubblewrap and still fly, so we avoid, by not flying over them. I hope this makes a good example of how when you break these things down they become very simple to answer.

I honestly could talk all day about this. I was an ISO Representative/Champion at my old job and I'm already getting involved with ISO at my new job!

 

[NathanSchool]

I would just add razor blade cuts as maybe a likelihood of A and risk level 3
move lipo fires down to a C or D and change prop activation up to a B or C

A is unlikely and D is likely.

 

[NathanSchool]

Made changes based on the most recent suggestions:

Anything else I should add?

 

[NathanSchool]

I will submit this to my supervisors soon. Do these values look good (A unlikely D likely and Risk 1 is mild while 5 is severe)?

 

[NathanSchool]

 

[mastermalpass]

I will submit this to my supervisors soon. Do these values look good (A unlikely D likely and Risk 1 is mild while 5 is severe)?

Yes for Risk, no for Liklihood; I would invert them to A being likely and D being unlikely.

 

[mastermalpass]

I must say I do like the choice of numbers for severity and letters for liklihood. A Risk rating of '4C' immediately tells you the liklihood and severity. Whereas a Risk rating of '18' is on a more linear scale.

 

[bisco]

'rubber or insulated clothing' would set a precedent

 

[dylanbeaudette]

I learned the hard way about propeller risk. In my excitement to get a model up in the air, I powered the model before the transmitter. There were three other people flying and the stray radio frequency interference was enough to cause the yet un-bound receiver to twitch. Control surfaces waved around and the prop started spinning. Before I could drop the thing it had cut me deeply on my pinky finger. Several lessons learned.

Transmitter on first, then model power, then propeller.

 

[bisco]

 

[PsyBorg]

Easiest way to mitigate prop cuts is to NOT put them on until ready to walk to the flight line.

Simple rule of the build tent.. If powered up in the tent (house / work bench ) then no propeller is allowed. When you are ready to walk to the flight line and the unit is unpowered for said walk THEN you can put the prop on.

The only time this needs to be not followed is for watt testing power trains on a securely mounted test fixture STILL avoiding being in range of a prop having any potential for spinning up.

 

[Bricks]

Mitigating prop cuts use a two switch system to arm. All this is mute when talking IC planes, throttle cut absolutely mandatory..