Whole house generator

[Koolau]

thanks for bumping this up. I will copy and paste a post of mine from another forum that is a graphic example of just how much CO is produced by a small 4 cycle gas engine.
"I went back to the big apartment job to write up the confined entry permit and give a hand with the pumps, about 2 years after we set the structures.
View attachment 50987
Things were going great and the atmosphere was testing good, until they started pressure washing the parking floor above.
As we all know, small engines have no emissions controls and put out more CO than a handful of clean running cars. Yeah Yeah, sure.
Today I got the demonstration.
This little Honda got that whole half a city block garage level above habitable levels, with huge fans exhausting the whole time.
View attachment 50988
We started the morning with ZERO CO on the meter, and suddenly it is over 25 and the alarm is squawking. I take a little walkabout and it is all bad, all over.
It is in the 25~35 PPM level, which is one hour max exposure. We get the crew above to cease with the pressure washing until we get done. In about 5 minutes the big garage fans clear it down below the alarm, and when I left it was back to zero again."

This is a certified Altair 4 gas meter that I get calibrated regularly. When I say huge exhaust fans, I mean the 6' diameter fans built into the structure for this purpose. Shortly after my alarm went off the entire building fire alarm started going off based on the CO detectors in the basement.
Set all the politics aside and look at the science. That little Honda defeated a parking garage's ability to cope, a place where a handful of cars could be running and moving. They really do put out the CO!
All it takes is a window open on the far side of a home and a bad door seal at an outside door to draw in enough CO from a generator to ruin your day. It does not have to be in the garage or the home to do it.

Can you imagine the cost of fitting all those little engines with catalytic converters?

 

[skyking1]

^ Hence the move to battery powered equipment. ^
It is a natural progression as mowers and things wear out. I know that personally I am down for it, just based on the noise change alone.

 

[Walt34]

Thank you for that write-up. Hopefully it'll save someone from making a fatal mistake.

 

[Koolau]

^ Hence the move to battery powered equipment. ^
It is a natural progression as mowers and things wear out. I know that personally I am down for it, just based on the noise change alone.

Yeah, now that the battery technology has evolved, it's time to convert to quieter, safer electric mowers (trimmers, etc.)

 

[skyking1]

Thank you for that write-up. Hopefully it'll save someone from making a fatal mistake.

you're welcome. I have used that meter for confined space entry requirements, and both times it has gone off in anger, the whole level I was in was bad, not just the manhole.
First time I walked up the ramp of a large parking garage all the way to the next level before it shut up. That was sobering. They had shut down the exhaust system for unknown reasons, and somebody could have taken the big sleep down there, literally.

 

[Koolau]

thanks for bumping this up. I will copy and paste a post of mine from another forum that is a graphic example of just how much CO is produced by a small 4 cycle gas engine.
"I went back to the big apartment job to write up the confined entry permit and give a hand with the pumps, about 2 years after we set the structures.
View attachment 50987
Things were going great and the atmosphere was testing good, until they started pressure washing the parking floor above.
As we all know, small engines have no emissions controls and put out more CO than a handful of clean running cars. Yeah Yeah, sure.
Today I got the demonstration.
This little Honda got that whole half a city block garage level above habitable levels, with huge fans exhausting the whole time.
View attachment 50988
We started the morning with ZERO CO on the meter, and suddenly it is over 25 and the alarm is squawking. I take a little walkabout and it is all bad, all over.
It is in the 25~35 PPM level, which is one hour max exposure. We get the crew above to cease with the pressure washing until we get done. In about 5 minutes the big garage fans clear it down below the alarm, and when I left it was back to zero again."

This is a certified Altair 4 gas meter that I get calibrated regularly. When I say huge exhaust fans, I mean the 6' diameter fans built into the structure for this purpose. Shortly after my alarm went off the entire building fire alarm started going off based on the CO detectors in the basement.
Set all the politics aside and look at the science. That little Honda defeated a parking garage's ability to cope, a place where a handful of cars could be running and moving. They really do put out the CO!
All it takes is a window open on the far side of a home and a bad door seal at an outside door to draw in enough CO from a generator to ruin your day. It does not have to be in the garage or the home to do it.

Please don't misunderstand me on this subject. CO is very dangerous and it's insidious as you don't know you're being exposed. But the numbers you mention (25 to 35 ppm) are not going to send anyone to the morgue. Here is the 1994 NIOSH take on CO.

CDC - Immediately Dangerous to Life or Health Concentrations (IDLH): Carbon monoxide - NIOSH Publications and Products

The OSHA PEL (Permissible Exposure Limit) is 50ppm - meaning most w*rkers can safely be exposed to this level for an 8 hour w*rk shift.

If you want to worry about insidious exposure to CO, think about smokers. IIRC their hemoglobin may be as much as 10% saturated with CO. (I've actually tested this out on some volunteer smokers vs non-smokers and, indeed found nearly 10% saturation in some smokers.)

CO is really bad, but probably not a generator hazard in a large open space with ventilation like a parking structure would have. It certainly isn't a major issue from an open window with a small engine outside. As always, YMMV.

 

[Out of Steam]

Yeah, now that the battery technology has evolved, it's time to convert to quieter, safer electric mowers (trimmers, etc.)

I dislike using a gasoline-powered mower enough that I am thinking about replacing mine with an electric one, even though the gas mower is working fine.

Battery life isn't a big factor, as I rarely mow the whole yard in a single day, though with thick zoysia grass, power is a factor.

 

[skyking1]

Please don't misunderstand me on this subject. CO is very dangerous and it's insidious as you don't know you're being exposed. But the numbers you mention (25 to 35 ppm) are not going to send anyone to the morgue. Here is the 1994 NIOSH take on CO.

CDC - Immediately Dangerous to Life or Health Concentrations (IDLH): Carbon monoxide - NIOSH Publications and Products

The OSHA PEL (Permissible Exposure Limit) is 50ppm - meaning most w*rkers can safely be exposed to this level for an 8 hour w*rk shift.

If you want to worry about insidious exposure to CO, think about smokers. IIRC their hemoglobin may be as much as 10% saturated with CO. (I've actually tested this out on some volunteer smokers vs non-smokers and, indeed found nearly 10% saturation in some smokers.)

CO is really bad, but probably not a generator hazard in a large open space with ventilation like a parking structure would have. It certainly isn't a major issue from an open window with a small engine outside. As always, YMMV.

It was 35 and climbing. This was not an experiment that I was ready to take with myself and the crew. I find it humorous that you would present to me OSHA and NIOSH publications when I actually work in the trades and am well versed in OSHA, MSHA, PELS, STEL, IDLH, and all that acronym soup that I had to study.
I have been certified at HAZMAT operator several times over the last 32 years or so.

 

[Koolau]

It was 35 and climbing. This was not an experiment that I was ready to take with myself and the crew. I find it humorous that you would present to me OSHA and NIOSH publications when I actually work in the trades and am well versed in OSHA, MSHA, PELS, STEL, IDLH, and all that acronym soup that I had to study.
I have been certified at HAZMAT operator several times over the last 32 years or so.

I was a CIH. My point was simply that those numbers do not present an immediate threat (IDLH - not even close) and long term exposure to those levels is not considered to be a significant hazard. Doesn't mean I think using a generator in a confined space wold be a good idea, but the data doesn't support anything approaching shutting down or evacuating. YMMV

 

[skyking1]

So what about the general fire alarm that was going off?
Once they shut down the pressure washer, the fans were able to draw down the levels and both my alarm and the fire alarm shut off. that was a 7 hp Honda, defeating a 900,000 cubic foot parking garage ventilation system. Those little engines can put out epic amounts of CO.

 

[DrRoy]

A few years ago after an outage, we bought a Honda inverter generator 3800 W. Haven't had to use it yet. (in MI)

 

[skyking1]

I have a pair of the 2000 inverter Hondas. The new house will get a modest battery bank for the essentials.
1) lights.
2) Fridge and freezer.
3) 1/4 hp hydronic circulating pump.

 

[Koolau]

So what about the general fire alarm that was going off?
Once they shut down the pressure washer, the fans were able to draw down the levels and both my alarm and the fire alarm shut off. that was a 7 hp Honda, defeating a 900,000 cubic foot parking garage ventilation system. Those little engines can put out epic amounts of CO.

Sorry, my expertise doesn't include fire alarms. As far as I know, they w*rk on "combustion products" in general of which CO is just one - but I'm not an expert. My only input is that CO (as bad and insidious as it is) is like any other "poison." It's effect is dose related. The air concentrations you mentioned would not be considered dangerous to empl*yees. But it is good that you actually checked the CO levels with a calibrated CO detector. That's the way to protect w*rkers - by actually determining their exposures during w*rk. Good on you.

 

[skyking1]

It's a requirement for confined space entry.