Carbon monoxide- an unscientific test- Part II

[highsierrabear]

Here is the second part of my post. Only allowed 4 pics so I couldn't get it into one post.

Continued from previous post:

Third test.
Here is the gas monitor in relation to where the saw is (about 12').




Here is the reading-

52ppm.

Each of these three tests set off the detector alarms within seconds.

At a fire, during overhaul, we use the CO detector to help determine whether it's safe to to overhaul without our breathing apparatus. The CO levels I was getting would mean that we would have to wear air tanks. FYI, it's a newer Drager 4-gas monitor ($2000+).

The test is flawed a bit because I was running the exhaust toward the monitor. Also, not everyong is running a big Stihl 440 type saw.

So what does this all mean?
No, the sky isn't falling. However, running a chainsaw does mean that you are breathing CO in significant amounts. We breathe CO as a result of lots of daily activities.

Chainsaw carvers use saws in a way that they were never intended. Chainsaw manufacturers never envisioned people using chainsaws in tents for hours on end. (Or running the saw upside down with the exhaust pointed in your face).

CO levels probably spike and fall constantly for chainsaw carvers. CO exposure is cumulative.

The good news is that CO levels in the blood stream return to normal if you return to fresh air. The bad news is that is takes hours for CO to leave your blood.

So what can you do?
Mitigate your CO exposure as much as you can.
- Carve outside under open skies whenever possible.
- If you must carve under shelter, have positive pressure ventilation available (e.g. fans pushing clean air into your carving space.
- Don't run a gas saw in enclosed spaces. Duh.
- Take frequent breaks in fresh air.
- Run a hydraulic or electric saw.
- Pay attention to your body. If you get headaches, tiredness, lethargy, dizziness, etc. Consider CO exposure as a possible source.

(CO exposure was one of the reasons I invested the big bucks in a hydraulic unit).

A note on cartridge respirators
Cartridge style respirators DO NOT filter out carbon monoxide (unless it's a supplied air respirator that supplies it's own air from a separate source). Remember that CO is a gas and not a particulate matter. Cartridge style respirators will filter out dust, and other particulate matter. Wood dust is a known carcinogen. Wearing a respirator is a really good idea.

Some resources-
OSHA findings
OCCUPATIONAL SAFETY AND HEALTH GUIDELINE FOR CARBON MONOXIDE

OSHA fact sheet
http://www.osha.gov/OshDoc/data_Gene...-factsheet.pdf

NIOSH fact sheet
Carbon Monoxide - NIOSH Topic Page

NIOSH chemical exposure summary
NIOSH Document: Pocket Guide to Chemical Hazards: Carbon monoxide | CDC/NIOSH

[Rwenzoski]

Hi Seirra, I seen your post on the carvingpost & I find this rather scary! I have always worried about how much CO we are actually absorbing doing this & makes me think of the effects of a couple of hundred saws running especially out of tune & crap gas/mix oil & petroleum chain oil, at the Vous all at one time in a small area. I know there where 55 people sick with headaches, sore throats etc. two years ago there! I quite often set up a tent to carve under if a lot of rain is in the forecast & I am even considering buying a large barn type fan as there isn't always a breeze to remove the CO properly. I try to raise the tent up as much as possible to allow more air flow but worried about breathing too much of this crap! I appreciate you posting this here also!
Thanks, Robbin
PS sure would love to hear about your experience with the hydraulic unit & have been wondering if a unit like this would run with Canola oil as the Hydraulic oil has some scary attributes also?

[Donsexton]

You have done us a good service thank you.

[btree50]

These results would also apply to small engine mechanics I woukd think. Kinda scary.
Thanks Sierra!
JimB

[quickcarver]

When I carve for a full day, or a few full days in a row, I take a break for a couple days , to a week, from the gas saws. The advent of electric, and hydraulic saws as carving saws is a remarkable aid in this battle, and one way to alleviate the problem.... I have had carbon Monoxide poisoning a few times, and it's worst in the heat, delirum may set in, and fatigue excellerates, and you could get hurt badly.
My doctor told me that it usually takes your body 48 to 72 hours to recover from over exposure to carbon monoxide gasses. She did how ever state that there are long term affects, such as emphazima, and some cancers can be ecellerated, or inflicted.
The smartest set up I ever saw was a carver wearing the Tyvec helment,with the respirator attatchment, that purifies the air you breath. THis unit is rather pricey, but I have used them in laquering applications, and in a room that you can't stand in without your eyes watering from the fumes, this respirator gives you clean breathing. THe common two cartrige repirators work as well, but you need a good seal, and you need to take occasional breaks, because carbon monoxide , among the other fumes generated by petro chemical burn off, will as well cause damage to the mucous membranes such as eye, and ear.
I have gotten eye, and ear infections from fine dust, brun off from metal smithing, and other gaseous applications. It's Hard to seal your eyes off without full head gear, so this expense may well be worth it. Fine saw dust is another thing that carvers battle, and it is the number one eye injusry of carvers( the scratched cornia). It happens after carving when you carry it around, and it rubbs in and under the eye lidd, as well it can cause white lung, or mild respiratory problems. Having an air compressor on hand , good ventillation, and eye ear , and some times breathing protection are your best friends if you carve a lot. electric saws , and hydraulic saws are my best friend, there are many models that can put out enough power, and RPM to do most work that can be done with a gas saw. And they are quieter too, so if you have close neighbors it's worth the investment.

[Backwater Bob]

Thank you Sandor. I got gassed out of a tent that was full of holes and had both ends wide open this year (my first year) and it is no fun.

I also found that my old lungs and hands just can't take the cold at all so I just went electric for the winter.

Are you going to Ridgway this year?

Bob

[bigEd_H]

Having been an auto technician for about 20 years, I can attest to the fact that one doesn't have to be in a tightly enclosed area to be affected by CO. Even with exhaust hoses connected to the tailpipe(s) of a running auto if the engine is out of tune it doesn't take long to have a high level of CO in the immediate area. CO level in the bloodstream is an accumulative thing, too. Repeated over exposure to CO is just as bad, if not worse, as continued exposure.

One thing that all chainsaw artists should consider too is the affect CO might have on your audience. Especially young children.

Safe and happy carving.

[quickcarver]

Good point Ed, I definitely have always considered ththe audience when carving. I am very picky about my fuel mix, and I don't run the saw at full revs for extended periods of time. It makes the show nicer for them too, if you stop every few minutes to look up andsmile, or wave to a kid, or even shut the saw off and interact with them. One advantage to never doing free shows is you aren't just there to sell your self , and your work. If you are guaranteed pay, you won't push so hard, and you won't be endangering your self, or others, because you are there for the crowd, not just there to sell to them.

[Just Carving]

Great post Highsierrabear! Kudos for bringing this matter up on the forum--it hadn't occurred to me--and I've been teaching injury prevention to emergency personnel for a long time now.

But I have a question on your test (BTW--unscientific tests can be the best kind--they open up a lot of doors):

Were you using positive ventilation, i.e. blowing air into the work site, when you were doing overhaul?

If you were, with regards to the CO monitoring, that may or may not have been a factor when using gas powered tools in an enclosed space. The reason I say may be a factor is because if the fan itself were gas powered, it could contribute to the CO value by blowing in its own exhaust. Regardless, the proven presence of CO in the open area in front of the fire station, even at 12 feet, should without a doubt be convincing enough about the perils of CO when using gas powered tools--regardless whether the exhaust was blowing at the monitor, or the size of the gas powered tool.

If you use electric powered fans (and power source is vehicle mounted generator or auxiliary generator placed well away from work site), then the positive ventilation would be a solution. I have always taught SCBA and monitoring should be mandatory when doing overhaul regardless of using gas powered tools or not. The residual gas by-products from the fire can be just as, if not more lethal. CO is one of the chief by-products of a fire and can be trapped in enclosed areas that could very well likely be the same areas that you are overhauling--even after the fire has been extinguished and the heat has been ventilated from the fire area.

With regards to wood carving with a chain saw, a simple box fan blowing on the work area could be part of the solution to at least reducing the amount of gases. Remember that CO is similar in weight to air. CO2 (Carbon dioxide--another by product of combustion) is heavier than air--and will displace oxygen and air. So, if you are working in an enclosed tent (which I also strongly discourage you from doing so), there should be at least some means of ventilation at the top and at the sides of the tent to have prevented the gases from building up. Otherwise, CO2 will exacerbate the CO presence by moving it closer to the "breathing area" of the tool operator.

One other point: In the case of a fire scene, the presence of heat will accelerate the rise of CO. So, a build up of heat from a gas powered tool will contribute to the presence of CO in the operator's "breathing space".

Finally, CO is a flammable gas. In the situation of a building fire, CO can become trapped in an enclosed room with the heat of a fire. Eventually, it and the other gas by-products will overcome the presence of oxygen since the oxygen will in all likelihood be consumed by the fire. The fire will "die down" and there will be glowing embers, heat and residual gases left in the room. A Fire requires three things: air, namely oxygen, fuel, and a source of ignition. In the event the door to the room where a fire has died down due to lack of oxygen were to be opened, there would be a rapid exhaust of heat and a rapid intake of fresh air, i.e. oxygen, causing it to mix with the exhausting CO--a flammable gas--a fuel--and the presence of a source of ignition-- the glowing embers--and the contents of the room--fuel--would explosively re-ignite into flame. This is commonly known in firefighting as a backdraft.

I tell you all this to emphasize that CO is not only lethal because of its ability to accumulate in the human body and disable the circulatory/respiratory function, but it is also a highly flammable gas--meaning that with the right combination of air, i.e. oxygen, CO, a source of ignition, and fuel (dare I say, wood chips and saw-dust) there could be a fire--explosive in a confined area (dare I say, an enclosed tent or garage)--or at the least, it would contribute to the acceleration of a fire. A CO explosion could yield the same results as a natural gas or propane gas explosion/fire. But a positive side to CO, is that just like natural gas and propane gas, it really takes a lot to get that right combination of CO, air, and source of ignition. And, even if that right combination did occur, the lethal effects of CO will have already killed anyone present in that environment without breathing apparatus.

Electric tools may be a better choice as long as the power source is electric coming via an extension cord coming from a building's electric outlet. If an electric generator is being used, then the presence of CO could still be a problem. Wind direction becomes a factor in ensuring the exhaust is being blown away from the work site, and to an open area. The same situation applies to hydraulic tools. A hydraulic pump powered by a gas engine would need to be placed in an open area and the operator would need to ensure that the exhaust was not blowing into the work space.

As with any tools that are used, there are safety issues that must be addressed. It's just a matter of awareness of the hazards, and taking precautions to ensure injuries are prevented.

Bob L

Note: My apologies if I overdid it with information, I never can resist a chance to get up on my injury prevention soapbox.

[BobD]

Great posts on this thread! This is something I never thought of. I really appreciate the time you all took to share this with the other members!!!

Bob