Time required for diesel fuel exhaust to disperse or evaporate 2

[neighbor lady]

I have a 1923 4 unit building with many doors and windows, the developer next door has placed a large 500 gallon diesel fuel generator 10 from the property line along with a 14 inch diesel fuel exhaust pipe directly horizontal and 15 from my second floor doors and windows , 10 feet from the property line, 12 feet up. The inspector says this is up to code so therefore it is safe. From what I have read this exhaust is highly toxic and hazardous to health. He says it will dissipate. From what I have read, it takes several hours to several days to dissipate. It will not take that long for these emissions to travel 15 feet and infiltrate my building before it dissipates.
Can anyone help me with this, it does not make sense. It also does not make sense that this is allowed per code books. The code treats a small home generator the same as a 500 gallon generator with the same recommendations of terminate at a safe point and 5 feet from doors and windows, which also does not make sense, the large unit will exhaust much more than a small one. I am thinking of appealing this decision. The picture shows the pipe with the orange cover on it, not finished, and the brown louvered box where I believe the fuel tanks are stored below in the basement.

 

[BridgeSmith]

From what I have read this exhaust is highly toxic and hazardous to health.

Where did you read that? People have been driving on roads in and with diesel vehicles for close to a century. Again, this is an emergency generator, which only runs during a power outage. If there's a power outage, keep the windows closed, and you'll never even notice that it's running.

 

[neighbor lady]

Osha, EPA, CDC. and many, many publications about the toxicity of Diesel Fuel exhaust is where I have read this, I have not read once that it is safe, only that it is very harmful to the respiratory system. It is one thing to drive along with windows rolled up passing diesel fueled vehicles and another sitting in your living room, or on the front porch breathing in emitted fumes. So, I tell my tenants, just close your windows on a day each month, don't use the front door, close the front living room doors, dont' go out on the balcony. I think they will not want to live there. I pay taxes, we should be able to have air free of diesel fuel at our homes, we are not in a car. Also, we had a horrible storm 3 years ago, we had no power for 3 days, a 1923 building is not air tight, the building would be full of emissions after 3 days. No one could live there.
I disagree with you about how toxic this is, it is not taken seriously enough. But , I very much appreciate your feed back on this. Thanks!!!

 

[SWComposites]

You need to find a local air quality expert to evaluate, probably someone from an environmental organization. And you will likely need to sue them to get anything changed. Asking a bunch of random folks on the internet isn’t really going to help much.

 

[rb1957]

You're right, noone is going to say that breathing diesel exhaust is healthy, an environment of 100% diesel exhaust would be toxic. But that doesn't mean that a 0.1% environment is also toxic.

If you have a diesel engine inside your house running 24/7, well that doesn't sound like a good idea.

If you have a diesel car in your garage, start it up, move out ... well that doesn't sound much different from a normal car.

Probably the most noticeable thing would be the smell, inconvenient but not toxic. If you do notice an odour, then an exhaust fan would probably fix it.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

 

[waross]

Does your city have a good neighbour bylaw?
I agree with you.
The situation is untenable.
I did a similar installation. Not my, design. I had no choice.
After a 2 hour commissioning run, there were so many serious complaints that the set was not run again until the exhaust was rerouted.
There may be possible criminal violations.
Assault with a noxious vapour?


--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[GregLocock]

Buy a long pipe and some brackets. Cheaper than a lawyer.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[neighbor lady]

These are all good comments that are very appreciated, this is very worrisome, have had the building since 1961. I feel that it is ruined by this, my rental situation will also be affected.
I suggested they take the pipe up ( 12 story) building) but they decline to do anything but ruin my place. I am sure we will have to sue, I will appeal this decision with the City of Dallas first. It is mind boggling that this is allowed by the ICC codes. I will contact an environmental testing company to get their input, thanks for that tip. Thanks for all of your responses, good to know what others think.

 

[rb1957]

is that a commercial property next door ? why would someone have a large diesel generator in their house/building (if not for commercial reasons) ?

If commercial in a residential neighbourhood, then it'd would've needed a by-law change (probably), and you may not have been aware of this going in. ie, the notice of the by-law change may not have been brought to your attention (and escaped your notice).

If commercial, is it noisy ?

You'll need allies before going to the city ... as I'm sure your neighbour does. I'd go to your local representative on council.

I wonder why this isn't considered to be a chimney ?

I wonder if a carefully directed hose might fill it with water ??

As a last resort, you could always close the windows on that side ... yes, I know you shouldn't have to.

I think one of the nastiest chemicals in diesel exhaust is CO ... you could get a detector/alarm (yes, you shouldn't have to ...)

Do you notice an odour ? Are you being alarmed by doing medical research on the internet ... just about never a good idea !!
If there is an odour, then there is some amount of exhaust getting into your house. If you can show a significant difference between when it isn't running (holidays ?) and when it is (work-week ?) then that is something for saying they are affecting your living conditions. particularly if the levels are higher than what the city health department allows.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

 

[waross]

For those who doubt the effects of diesel fumes, I have had first hand experience and the fumes are nasty.
In the case that I was faced with, the exhaust was not directly into the building but was directed past the HVAC fresh air intake of the building.
The HVAC system sucked in a small amount of exhaust fumes.
The fumes were barely noticeable, but after about two hours almost everyone had red irritated eyes and bad headaches.
If you find something on the internet that says that diesel fumes are safe, well that's the internet for you.


--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[neighbor lady]

The property just built with the generator is assisted living. The street was zoned multi-family, this project created it own zoning with a PD. designation. That is what they do in Dallas, so there are no rules they make their own rules. The generator is a Cummins 60hz 750 standby 680 prime EPA NSPA emergency tier 2. The specs. report exhaust at 888F. This is incredible heat so close, I do not see how this old mortar, brick will take this. I read that the exhaust should be in a chimney when temperature is 600 F. and above, IMC 511. There was no consideration of wind blowing this into my building, which it will. I read many times that wind should be considered in placement of the genset. The wind blows westerly very strong in this location. Thanks for your replies and suggestion, very helpful.

 

[zeusfaber]

One thing that hasn't really been addressed here is the question in the title of the thread.

It's worth understanding that diesel fuel and the exhaust from a diesel engine are two quite different problems.

The fuel is oily and, depending on the grade used, potentially quite smelly. If you spray it about, droplets of liquid are inclined to stick to surfaces and then evaporate slowly, so it stays noticeable for a long time. I suspect this is what gives rise to the "several hours to several days" you've read about.

The exhaust from burning diesel is different: It varies a bit depending on how modern the engine is and the grade of fuel (especially the sulphur content) that's being burnt, but you're looking at five different groups of constituents:

First, and by far the greatest proportion, is hot air mixed with water vapour. The water vapour may condense out into a white cloud downwind of the exhaust, that then re-evaporates. All this is harmless.

The second, and this is unavoidable, is CO2. There will be a lot of this when the machine is running, though it will dilute in the wind on its way over the fence. As a simple gas, it will clear from inside your property as quickly as you ventilate the place with clean air. If you measure high levels of CO2 inside your property, it's as likely to have been breathed out by the occupants as to have come in from outside - it's not unusual to find CO2 levels of 1000 ppm inside an office space (compared to 400 ppm outside). Not really harmful at those levels - in the UK, the 8 hour occupational exposure limit is 5000 ppm.

Third is a collection of trace gases. Primarily SOx, NOx and CO. How much of each of these you get depends on the quality of the fuel and the design of the engine and its exhaust system. Like CO2, they will dilute a bit in the wind and will clear quickly with ventilation. SOx makes the exhaust smelly, is driven by fuel quality and can be associated with particulate problems (see below). In larger quantities, NOx is the stuff that makes your eyes water and CO is responsible for the headaches Bill was talking about. At that sort of level, they're unpleasant but the symptoms resolve when you remove the contaminant. At much higher levels (and you might achieve this by breathing pure, undiluted, exhaust), CO can kill you quite quickly.

Next and, with a modern, properly maintained engine and suitable fuel you should really see almost none of this, is unburnt fuel and soot. If you get this, it does have the potential to stick to surfaces and to hang about a bit. Distinct from condensed water vapour, this takes the form of smelly blue or black smoke. Anything beyond a quick puff at startup suggests a machine that isn't in a fit state to minimise any of the other contaminants either.

The other one to be aware of is particulate (you may see it referred to as PM10 or PM2.5) In many respects, this is quite like the trace gases - it will dilute and ventilate quickly. Modern engines with modern exhaust systems burning low-sulphur fuels generate a lot less particulate than traditional diesels. The health effects of inhaling particulates are much less immediate than the other contaminants, but much more likely to be long-term and cumulative. On this side of the Atlantic, a growing perception of the health problems caused by particulates has reversed what was a popular trend towards driving diesel cars. This might well be the element you want to pay most attention to.

Worth highlighting the importance of dilution. The key thing is what enters your property rather than what comes out the exhaust. How quickly and thoroughly the exhaust gases get diluted depends on a few things - including the design of the outlet and the temperature of the exhaust plume (the high temperature actually works in your favour) as well as the wind. The plume won't be at anything like 888F by the time it reaches your wall - but you ought to bear in mind that the strong westerly wind you mention is your friend; if you're going to have problems, they will be at their worst on days when there is no wind to help dilute the exhaust. If you get air-quality monitoring done, ensure at least some of it is arranged for a day when no wind is forecast.

 

[neighbor lady]

Thank you for this explanation of this process, this is good to know. This is extremely helpful as all of these replies have been. I am acutely aware of being careful of hazardous air around me having survived lung cancer I am sure from many years of old house remodeling all hands on all phases. Thanks!!!

 

[rb1957]

Oh, sorry to hear that (lung cancer), but happy that you're a survivor (so far !). This clearly and sensibly makes you more sensitive to this type of thing.

I don't think the exhaust plume is at such a high temperature, I think it is noted so they can define the gas composition.

It is a shame that they are not being a "good neighbor" (your spelling !) and adding a chimney ... seems a relatively simple thing, but they are probably operating on a "shoestring" (wonder where that expression came from ?) and might say "we can spend $X on a chimney, or on helping our clients", which makes a difficult case.

One way out is to close the window ... yes, you shouldn't need to, but ...

If you're worried about resale value, talk to an estate agent ... but I doubt you'll get make return for this; it is what it is now !?

If you're worried that the unit will impact your health, collect data now (before it starts up) ... air quality. But this'll be quite expensive.

But it is built. Possibly one way is to offer to pay 50% of the chimney costs ? I think the chimney would address your concerns.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

 

[LittleInch]

Have you got a more up to date photo?

A few things on your post which might help when you're taking about this to people.

The size of the fuel tank is not relevant. What you want to quote to people is the size of the generator ( looks like 750hp) and the size of the engine and exhaust pipe.

You can then eq it ate that to something like a large semi tractor unit.

Also are you predominantly down wind?

How tall is your building?

But agree with a lot of what zeusfaber pointed out. If from a window you're looking at a large exhaust pointing at you from 5m away that's not great, but don't believe all you read.

The exhaust though really should be pointing up and at least a high as your building.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[neighbor lady]

Thank you for your reply, I have done so well health wise to recover from this scourge of lung cancer by having been a swimmer 1 hour a day for 25 years before I got this, I was strong. I will post an up to date picture, my building is 2 and one half story, the exhaust pipe terminates next door in height to the top of my first floor , not high enough to evade me. I am down wind. I have tried to get them to exhaust in a chimney over head, this would alleviate many concerns, they just will not do so, they don't care.

 

[waross]

750 Standby, would be 750 KVA. That will require a minimum of 800 HP.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[BridgeSmith]

It looks like they have moved the exhaust from where it was in your earlier thread, where it was on the side of the building pointed down. I assume that the current exhaust location is what's shown on the end of the building, pointed up, and covered by the Home Depot bucket.

Obviously, it's not in use yet, so now is the time to buy some air quality metering equipment, so you have a baseline for your air quality, and you can document the effect on the air quality in your building when the generator is used. At this point, that may be the only way that you can make them change it - provide proof that it has a detrimental effect on your air quality.

The Best Air Quality Monitors to Keep Your Family Safe and Healthy, Tested

 

[zeusfaber]

If you're going to buy yourself an air quality monitor, choose one which measures the right things. People buy monitors to address a wide range of concerns and the manufacturers often optimise their product to address a particular market segment. To address your particular issue, important things are likely to be:

CO2. I suspect this is the thing where you're most likely to be able to measure a difference. Don't use it as your only analyte though - the occupants of your house are a significant source of CO2 and the Neighbours will claim that that's what you're measuring. Make sure the detector actually does measure CO2 - there are some cheap ones out there that actually measure VOCs (volatile organics) and then report that as a CO2 equivalent. That might just about pass muster for some jobs, but is useless in your context. Look for something with a NDIR (non-dispersive infra red) sensor - these are good enough without being eye-wateringly expensive.

Particulate (PM10/PM2.5). This will get the attention of your Neighbours' legal advisers. Once again, don't make it your only analyte - particulate is quite difficult to measure consistently as everything you do anywhere near the sensor throws up clouds of the bloody stuff.

CO. If you can show an increase in this, you really are going to attract attention and, provided people aren't cooking on gas in the same room, the reading is unlikely to be disturbed by domestic activities.

Nitrogen dioxide (NO2 - the main NOX constituent) is a "nice to have" as it's a relatively specific marker for diesel exhaust.

Other things like VOCs, Radon, Formaldehyde and Ozone address somebody else's problem, not yours.

Needless to say, the only monitor in the article BridgeSmith posted that covers the analytes you want is pretty much the most expensive (the uHoo Smart Indoor Air Quality Monitor). I've got no experience of their products (I've been quite impressed with Temtop's consumer products, but nothing in their range seems to cover CO).

I'll second BridgeSmith's point that the the time to start monitoring is before you have a problem. Getting a good baseline is critical.

A.

 

[rb1957]

something to measure the smell ? diesel droplets ?

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.