Chain saw accidents.

[Ed.]

Hi guys, this is probably a dumb question but I am interested in finding out the mechanics of how chainsaw accidents occur, as a lot of you guys do this for a living and there is much more logging in your part of the world, so you would be much more aware of these things.

Now excluding all the obvious ones like kickbacks, trees falling down on a worker, over reaching, sawing without a good balance on the ground and falling on top of the saw. Just the bare mechanical basics, do they occur when a saw chain breaks and the broken end whips around the bar tip in a large arc or when a chain comes off a bar, that sort of thing and how often does this sort of thing happens? Hope this sort of makes sense!

[beenthere]

Can't say, as I've never been injured by a chainsaw. (knock on wood.. old saying).

Are you excluding the obvious ones, so just want the "un-obvious" ?

What is leading up to the question. Maybe that will help figure out what you are after.

[Ed.]

Hi Beenthere, how this started was I was talking to a young bloke(23)  who is a chippie (carpenter) and his boss likes to take shortcuts where possible, on a building site this chippee was working at, there was a couple of trees that had to be removed, so instead of getting someone who knows what they are doing , the boss just went to a hire place and got a chainsaw and told this chippie to cut them down, apparently the chain was very blunt, no safety gear, no training in chainsaws ect. 

Anyway I was telling him that I would have refused due to the safety aspect and tried to tell him about the dangers of  using blunt chain saws, no safety gear ect. ect. and I got to wandering about how frequently accidents occur due to actual equipment failure and not the obvious ones I listed earlier as a lot of those causes can be minimized or removed with a bit of care.

I do not do much chainsawing myself and have never seen an accident ( touch wood also) although I own 3 chainsaws. But I was wondering about mechanical failures such as what happens when a chain breaks or gets pinched and comes off the bar, I would assume that it wraps itself around you if you are felling and slashes you or does the chain grabber work well and are there other causes that can lead to major injuries? When cutting on the ground you can always remove your body from the line of damage , but this isn't possible when felling if it wraps around you. So just curious about the causes and how common they are.

[HolmenTree]

Ed, in all the years I made a living  with a chainsaw and all the thousands  of times I have derailed a chain, I have never had a chain wrap around any part of my body.
Not even a cut.
When a chain derails even at the highest  speed,  the drive links instantly  disengage from the drive sprocket  and the chain stops rotating when making contact with the saw. Whether it's  the chain catcher, sprocket  cover or rear handle guard.

[Ed.]

Hi HolmenTree, that is good to know, I assume that the same result applies when the chain breaks or is that different? So I take it that most of the casualties are from kickbacks and that sort of thing?

[Spartan]

Never had a mechanical related injury.  Would expect they are very uncommon.  Most i know happen by user error or outside uncontrollable events.
Although, some mechanical failures would probably have to fall under user error if it has to do with maintenance or inspection before use, that kind of stuff.

All my injuries were either stupid stuff or chance, none were mechanically saw related.

[JohnW]

I think, by definition, your question is almost impossible to answer.  Generally, chainsaws are so distructive, and logs are so dangerously heavy, that those who deal with them quite natuarly have a little respect.  Accidents happen due to the unexpected and unforseen.  If we could forsee them, we could answer your question.

Everybody that's cut down and cut up a couple trees came close some place or another.

[HolmenTree]

Ed to answer your question same scenario,  chain breaks the drive sprocket  instantly  disengages from the drive links. Chain stops. No whipping or flailing.
Kick backs by far are the greatest  danger of chainsaw operation next to struck byes from trees or parts of a tree.

[Ed.]

Thanks guys for your responses, they answered my questions.

Cheers

Ed.

[so il logger]

Ed to answer your question same scenario,  chain breaks the drive sprocket  instantly  disengages from the drive links. Chain stops. No whipping or flailing.
Kick backs by far are the greatest  danger of chainsaw operation next to struck byes from trees or parts of a tree.

I may have to respectfully disagree about chain breakage not causing flailing. If it breaks when it is in the right spot it will flail or whip. I know from experience. But yes most injuries from operating a saw are from the tree or limbs or what have you. Logging or tree trimming is a dangerous job. If need be I guess I can have the wife take a pic of the scar's on my arm that caught a broken chain. It can happen

[Ianab]

Yes, it can happen for sure. Not often, but often enough that modern saws have some sort of "chain catcher" down under the bar to reduce the chances of it happening.  If it never flicked off in a dangerous way, there wouldn't be any need to fit the catcher.

[HolmenTree]

I'm wondering if this flailing broken chain was driven by a spur gear sprocket?
Another  few questions  what model of saw . How did the chain break and was a chain catcher and rear handle guard on the saw?

[BradMarks]

I've thrown(derail) a number of chains, but never had one break while operating. Sometimes you might get "stung" by it, but never anything serious. But it is why I prefer chaps that have legs sewn together in the crotch area. A little less mobility but a lot more protection.

[sandsawmill14]

we used to break a lot of chains when we were running the old big saws(1050 homelites and a couple 100cc macs)  but they would normally just shoot out through leaves off end of bar.  i loved those old saws i still have a 1050 and a 1020( plus a few others) i might see what it would take to get them running

[so il logger]

I'm wondering if this flailing broken chain was driven by a spur gear sprocket?
Another  few questions  what model of saw . How did the chain break and was a chain catcher and rear handle guard on the saw?

It was a rim/drum on a 660, 24in oregon bar and 75lgx chain. The chain catcher was long ago broke off, seems common. Yeah the rear handle was on the saw, I was limbing a water oak that was riding kind of high from limbs holding it up so the saw was above my head. The chain broke and it whipped back and down slapping my arm. I also agree that every other time I have had a chain break it has gotten thrown out away from the tip of the bar. Just saying never say it cant because believe me it can. 

[HolmenTree]

Same here the few chains that ever broke on me just fly off the end of the bar and laid on the ground.
When you were limbing that tree above your head the limb may have deflected the chain down and back at you. Chain catcher probably wouldn't  have helped in that situation  anyways.

[so il logger]

That's what I figure happened as well, the limb probably deflected it toward me. But figured I better throw it out there that it has happened. May have broken in the right spot like on the bottom side of the bar I honestly don't know but it wasn't a bad injury so that is what matter's  8)

[Ianab]

A chain doesn't need to hit you "hard" to leave a mark, the sort that needs stitches at least. Same as a kicback where the chainbrake has activated can still cut you, just no where near as bad as a chain that's still running.

Now 99% of the time it wont get you because it flicks off the front of the saw. But that means 1% of the time, it's going to come your way. Then you hope the chaincatcher, your chaps, and good body position keep you safe.

[so il logger]

A chain doesn't need to hit you "hard" to leave a mark, the sort that needs stitches at least. Same as a kicback where the chainbrake has activated can still cut you, just no where near as bad as a chain that's still running.

Now 99% of the time it wont get you because it flicks off the front of the saw. But that means 1% of the time, it's going to come your way. Then you hope the chaincatcher, your chaps, and good body position keep you safe.

X2... I wound up with 12 stitches out of my deal, the way my luck runs if it can possibly happen it will happen  :D I am laid up at the present time because of another felling accident  :D

[longtime lurker]

Hi Beenthere, how this started was I was talking to a young bloke(23)  who is a chippie (carpenter) and his boss likes to take shortcuts where possible, on a building site this chippee was working at, there was a couple of trees that had to be removed, so instead of getting someone who knows what they are doing , the boss just went to a hire place and got a chainsaw and told this chippie to cut them down, apparently the chain was very blunt, no safety gear, no training in chainsaws ect. 

So our carpenter is smart enough to know the saw is blunt but not smart enough to stop and sharpen it. Why didn't he sharpen it? Would he stop and sharpen/ change blades on his circular saw when it gets blunt or does he just keep going until the boss tells him to fix that too?
Why didn't he advise the boss he had no chainsaw experience? And y'know... PPE is a must at the idiot level, which is where I'd put 99.9% of the general populace when it comes to chainsaws, regardless of their experience or training level. All employees have the right to say "where's the PPE", all supervisors have the right to fire based on refusal to wear it.

Honestly, it should be mandatory for hire places to send at least chaps with a hire chainsaw... but it aint. In a workplace however no-one is going to get fired for refusing to do a job without PPE. Personally I believe that hire places should have an obligation to send appropriate PPE with any piece of equipment they hire out as part of the hire.

Anyway I was telling him that I would have refused due to the safety aspect and tried to tell him about the dangers of  using blunt chain saws, no safety gear ect. ect. and I got to wandering about how frequently accidents occur due to actual equipment failure and not the obvious ones I listed earlier as a lot of those causes can be minimized or removed with a bit of care.

The major cause of death in professional forest workers is from falling objects, per the last WHS major study into what is Australia's most dangerous industry. Injury due to chainsaw is rare, and also in that you need to add that at after certain level in the professional industry we can actually get exemptions from wearing PPE (specifically chaps) because the risks associated with wearing it are higher then the risks of an injury from a saw. So at the pro level many dont wear chaps and we still dont get hurt by chainsaws.
Chaps save your legs from risks of kickback, flying chain etc. What they really are is insurance for those who through lack of knowledge encounter kickback... or dont know enough to maintain their gear. Kickback is the result of operator error each and every time it occurs. (Hard hats of course are there to make it easier for the paramedics to scrape your brains up.)

I do not do much chainsawing myself and have never seen an accident ( touch wood also) although I own 3 chainsaws. But I was wondering about mechanical failures such as what happens when a chain breaks or gets pinched and comes off the bar, I would assume that it wraps itself around you if you are felling and slashes you or does the chain grabber work well and are there other causes that can lead to major injuries? When cutting on the ground you can always remove your body from the line of damage , but this isn't possible when felling if it wraps around you. So just curious about the causes and how common they are.

Chains come off for a number of reasons. Most common is incorrect chain tension: ie the operator keeps cutting when the chain is visibly loose. Thats caused by a fault know as laziness: ie the operator was too lazy to tighten it.
Significant causes of loose chains are operator keeps cutting with a blunt chain, and the excess heat generated by that makes the chain stretch. Thats caused by a fault know as laziness also, cause the operator was too dammed lazy to stop and sharpen it.
Chains dont just fall off the bar rails or fly apart without reason. When a chain does jump, it mostly wraps upwards and back into the clutch brake guard/front hand positions. Other then that it is most likely to strike you in the legs.

I don't mean to sound difficult here - but I get annoyed when people screw up then go looking for someone to blame rather then accepting responsibility for their own wrong choices. Chainsaws are not inherently dangerous things: like firearms its the idiot on the end of it that makes them dangerous. At least an idiot with a chainsaw is only mostly a danger to themselves.

[so il logger]

I do believe my instance of the chain breaking and actually hitting me was probably because of a chain that had been bent somewhat because of a pinch soon before. Was not dull or loose chain for sure. Probably a weak tie strap from being pinched and bent a little. Longtime lurker are you a faller???? Internet only teaches so much, not all  accidents  are idiot related.

[HolmenTree]

Longtime lurker are you a faller???? Internet only teaches so much, not all  accidents  are idiot related.

The comments about hard hats are only good for paramedics to collect up brains, leg protection are not worn after a certain level of professionalism  tells me everything :D

[longtime lurker]

Once upon a time I thought I was a serious professional feller - nowadays I only do the 1500 odd ton of logs a year we require for our own mill. But I figure that gives me the right to an opinion, and after 30 years in the industry I'm still here so I surely have earnt the right to voice it.

Along the way I've had one chain break - idiot had got distracted making chains and hadnt spun the rivets properly. Seeing as I make my own chains....
Maybe I've been lucky, but maybe its because I run .404 chain too - little bit heavier, little bit stronger perhaps.

Had a few chains come off the rails but  - with the exception of the days when I was running an 090 with a 42"solid nose that used to get hot in the kind of cuts where that isn't an overkill saw - in each case dispassionate analysis was that I should have stopped and tightened the chain up because it was getting hot and I could see it stretching.

Had a few belts to the head from hung up stuff but with one exception that was a freak incident I'd say it was because I probably should have been using the big yellow wedge instead of being underneath what I was. Seen a guy get really messed up by a falling branch but he was just out tree marking and - freak accident. Hard hat is the one piece of PPE i take seriously but y'know... most fatalities in this industry come from stuff falling out of trees so it can't be too effective can it?

Been cut once... took the top off my thumb with a top handle saw ( holding branch in one hand and saw in other) clearing out the inside of a culvert full of flood debris. Idiot place to be in the first place.

Chaps here will kill you. Cutting your leg might kill you - but try wearing chaps when its 100 degrees and humid like the inside of a sauna and dehydration will get you first. That would be a proven fact. This aint the temperate zone guys - but you're welcome to come visit anytime if you want to prove a point.

[JohnG28]

Different parts of the world, different sets of standards. Joe_indi has posted some wild videos of guys cutting rubber trees in India, shorts and sandals and ms460s ripping away!

[HolmenTree]

Different parts of the world, different sets of standards. Joe_indi has posted some wild videos of guys cutting rubber trees in India, shorts and sandals and ms460s ripping away!

Yes but with the over population in India workers are a dime a dozen.........sorry Joe please take no offense.

[bill m]

I don't care how hot it may be, I will be wearing my chaps. Just will be taking more water breaks to stay hydrated.

[sandsawmill14]

safety gear is very important but no where near as important as common sense and proper training     sorta like artificial intelligence is no match for natural stupidity  :D :D :D

[foresterstan]

most accidents I have seen are from taking shortcuts on safety and maintenance, and being in a hurry. 
good gear and a sharp saw and some patience are pretty good safety precautions...

[John Mc]

I've heard of - or seen the results of - two categories of accidents that seem to make up an awful lot of accidents:

• people taking shortcuts on safety, as foresterstan mentioned. This can be either a conscious decision, or simply a lack of knowledge.
• fatigue or dehydration - funny things happen when you are tired, or your brain isn't firing on all cylinders due to dehydration. So many stories include something like " I was on my last tree/splitting that last log/finishing up my last load"

[sawguy21]

"So our carpenter is smart enough to know the saw is blunt but not smart enough to stop and sharpen it. Why didn't he sharpen it? Would he stop and sharpen/ change blades on his circular saw when it gets blunt or does he just keep going until the boss tells him to fix that too"
I have to take exception to this statement. The guy is a carpenter, not a chain saw operator. He has obviously had zero training using a tool that is much different than a circular saw. How many know how to properly sharpen a chain? So change the chain for a sharp one. Did he have a spare and know how to properly install it?
This whole scenario is an accident looking for a place to happen. Unfortunately shoddy operations like this are all too common, the workers are either too timid or too desperate for work to speak up. I don't know how strict the Australian authorities are, maybe lack of enforcement is also an issue. I understand they cannot be watching everyone all the time but maybe tighter regulations on who can perform this type of work are in order. Nobody dislikes government intervention more than I do but certain standards have to be set and met.

[Ed.]

The Australian authorities only get involved after the fact if there is an accident. There are probably existing rules to cover the safety and training requirements but I think that his employer seems to think he can get away with it. This chippie doesn't know how to sharpen a chainsaw nor had a suitable file to suit the chain. Needless to say I think that the tool hire mob would probably be liable (maybe?) for hiring  out a blunt chain saw, but I suppose that they may have a getout clause in the fact that it is up to the hirer to know how to use a power tool and supply their own PPE if they are hiring one out. I personally think that if an employer wants a worker to use a particular piece of machinery then it is the employers duty to ensure that the equipment is safe and that the worker is properly trained. There are laws to require this to happen but there are also too many shoddy employers who think that they can get away with it.

Unfortunately most workers don't want to rock the boat as unemployment here is high so most toe the line but as I said before, I wouldn't have used it, however as he is young and just finished his apprenticeship so probably not experienced enough able to stick up for his rights.

[Hitchcock Woods]

Mechanical failures are never a problem from a saftey aspect from our perspective if the proper gear is worn.  Bars getting pinched happens to everyone (especially bucking IMO).  Biggest saftey concern we have here is when trees get blown over in storms across trails and we have to clear them.  Big limbs can bend a lot and have a tremendous amount of pressure on them when the main weight of the tree is pushing that limb against another tree.  We do "accordion" cuts where we make multiple cuts on a joint that only go ~half way through on a lead to relieve a lot of the pressure.  I once saw a Longleaf limb move 20 feet laterally when i was cutting it, and that would ruin your day if it hit you  .

[John Mc]

I agree, Hitchcock Woods. Storm damage clean up is one tough job. You've got to be really good at reading the pressures on the trees. There are some interesting cuts you can make when you are not sure - I learned a few new techniques in a "storm damage clean-up" class I took a few years back. I should have taken better notes. I've forgotten a lot of what they showed me - I needed to use it a few more times right after taking the class in order to drum it into my head.

[John Vander]

Here in Japan chainsaw accidents are common due to lack of training and lack of PPE. Japan gets very hot with high humidity, but I wear my PPE cause if I get an accident it means I'm out of work for a while with added expenses (medical). My one friend's son (who thinks he knows everything) did some firewood cutting the other day and exerienced a serious kickback that flipped the saw out of his hands and it came back at him, cutting his left arm half way through. My friend himself has been cut several times too. One time he cut his leg (which wearing a pair of chaps could have easily prevented). Funny thing is right after that he went out and bought a helmet... ???