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Photograph of - is this heating oil running across the basement floor? Notice the abandoned oil line at the furnace? Oil tank safety warnings
Fuel Oil & Heating Oil Storage Tank Explosion & Other Hazards

Oil storage tank safety hazards:

This document discusses safety issues involving residential and light commercial oil storage tanks and oil tank leaks, fire hazards, large oil storage tank fume explosions, and other risks.

Beyond the costly problem of actual leaks from oil storage tanks, oil leaks into buildings, and leaky oil piping, this document lists other important safety or oil-fired equipment concerns in home and light commercial heating oil storage and piping systems.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

OIL TANK & HEATING OIL EXPOSURE HEALTH, FIRE, & SAFETY HAZARDS LIST

Fire & Explosion hazards of No. 2 home heating oil and No. 4 fuel oil. List of fuel oil safety hazards and detailed articles on each. Safety warnings concerning residential and small commercial heating oil storage tanks. Links to articles on other oil heat safety concerns, measures, controls, devices.

Oil and LP/Natural Gas Tank & Fuel Explosion Hazards

"Deaths Draw Attention to Dangers of Oil Tanks" reported the New York Times 13 April 2010. The explosions and deaths of (usually) teenagers described in the NY Times article did not involve residential oil storage tanks.

The deaths reported by the Times have been associated with larger outdoor above-ground storage tanks often found in residential areas in the rural southern and western U.S. Accidents, explosions, and sometimes deaths occur when oil (or natural gas) vapors, released through a storage tank roof hatch are ignited by a spark from a cigarette, firework, cigarette lighter, or gun.

"The explosions are so violent that victims' bodies are often thrown up to 200 feet from the tanks." the Times reported. Property owners where these fuel storage tanks are installed are encouraged (sometimes legally required) to post adequate safety warning signs and access control fencing.

COMMENT: Why would a 14-year-old Springtown TX teenaged boy drop burning paper into an active fuel storage tank?

OPINION: Because teens, believing they are invincible, try stupid stunts. Attorneys may argue that unprotected outdoor fuel storage tanks are an attractive nuisance to teens.

What is the Risk of an Explosion or Fire From No. 2 Home Heating Oil Fumes?

Heating oil needs to be heated to 140 degF and sprayed or atomized in order to burn. Some oil sales and delivery companies inform us that unlike LP or natural gas fumes, heating oil fumes are not combustible. [Oregon Oil Heat Assoc. and others].

Indeed, in oil burner service school, a demonstration of the low combustibility of home heating oil was demonstrated in the classroom (a huge garage) by tossing a lit match into a coffee can of No. 2 home heating oil. The match went out.

At a typical home heating boiler or furnace that burns No. 2 home heating oil, the oil is ignited by a combination of conversion of the fuel to a fine spray through an oil nozzle (typically at 100 psi or higher), and the presence of a pair of high-voltage electrodes that produce a continuous spark to ignite and keep lit this spray of fuel. The hot sides of the oil burner's combustion chamber liner help complete the combustion of the fine droplets of oil that may miss the flame pattern and stray to the chamber sides.

But the difficulty in igniting a coffee can of home heating oil in a garage is not the whole story. a review of an example MSDS for No. 2 Fuel Oil (home heating oil) such as this example from the responsible professionals at Hess Corporationdiscloses the following indication that Fuel Oil Fumes are indeed combustible:

FIRE AND EXPLOSION HAZARDS of No. 2 Home Heating Oil

OSHA and NFPA Class 2 COMBUSTIBLE LIQUID (see Section 14 for transportation classification).

Vapors may be ignited rapidly when exposed to heat, spark, open flame or other source of ignition. When mixed with air and exposed to an ignition source, flammable vapors can burn in the open or explode in confined spaces. Being heavier than air, vapors may travel long distances to an ignition source and flash back. Runoff to sewer may cause fire or explosion hazard.

And a review of an example MSDS for No. 4 Fuel Oil (heavier oil used in industry) contains a similar warning, with an explanation about a reduced explosion risk for this heavier fuel: [The Hess MSDS for No. 6 Fuel Oil contains the same warning as below.]

FIRE AND EXPLOSION HAZARDS of No. 4 Heating Oil

Vapors may be ignited rapidly when exposed to heat, spark, open flame or other source of ignition. When mixed with air and exposed to an ignition source, flammable vapors can burn in the open or explode in confined spaces. Being heavier than air, vapors may travel long distances to an ignition source and flash back. Runoff to sewer may cause fire or explosion hazard.

CAUTION: flammable vapor production at ambient temperature in the open is expected to be minimal unless the oil is heated above its flash point. However, industry experience indicates that light hydrocarbon vapors can build up in the headspace of storage tanks at temperatures below the flash point of the oil, presenting a flammability and explosion hazard.

Tank headspaces should be regarded a potentially flammable, since the oil’s point can not be regarded as a reliable indicator of the potential flammability in tank headspaces.

The bold font (our edit) in the MSDS text above may explain the tragic explosions and deaths reported by the NY Times to have occurred around oil storage tanks.

OPINION: the risk of fire or explosion from normal use of No. 2 home heating oil inside private residences, including during oil tank fill-up, heating system service procedures, or minor drips at an oil pipe fitting, is asserted by home heating oil delivery companies to be very low, and we agree that it is likely to be considerably less than the hazards discussed above where larger storage facilities and a variety of fuels are involved.

Articles About Heating Oil Storage Tank and Oil Piping, Control, Exposure, and Management Safety

Fusible link oil line valve (C) Daniel Friedman

 




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Reader Comments, Questions & Answers About The Article Above

Below you will find questions and answers previously posted on this page at its page bottom reader comment box.

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2018-05-31 - by (mod) -

Dave

I have seen and also used storage shelving over the oil storage tank used to store light-weight items that don't risk damaging the tank or piping.

The risk is that a tank fill or vent pipe leaks during fill-up and destroys what's nearby.

On 2018-05-30 by Dave T

Can I safely store items on top of indoor tank? I have some wood (2x4s etc) that I would like to store keeping them well away from the site gauge and pipes.

On 2017-09-06 - by (mod) -

PC

Please find your question and my detailed reply at the end of the article above.

Let me know if you have further questions; use the page bottom CONTACT link to send us photos of your oil tank for comment if you like.

On 2017-09-06 by PC

Can I remove an oil tank by cutting it with a reciprocating saw?....Is there an explosion hazard?

On 2017-01-26 - by (mod) -

Brent,

I think it can be very difficult to retrieve a brass object from the bottom of a large oil tank, since it will be difficult to hook it, and it's not magnetic so you're not going to pick it up with a magnet. However particularly if the oil is being taken out from the top of the tank then most likely the fitting will lie harmlessly on the very bottom of the tank where it doesn't interfere with anything.

On 2017-01-26 by BrentH

Hi ,what can someone do in an accident where someone accidetally drops a material inside a big storage tank full with fuel/oil? Material such as brass fittings?

Question: is the smell from an oil tank in our home dangerous?

(Aug 1, 2016) Sandy said:

We are thinking of buying a home. The home had an abandoned fuel oil tank. They say there were no spills, but because there was so much fuel oil left in the tank that there is now a strong smell. Is this dangerous? Will the fumes ignite when the gas furnace is turned on?

Reply:

Regrettablby,

1. What "They say" about oil spills is of no use to you whatsoever; it is not reliable, may be incorrect, and is absolutely no guarantee that you won't face a significant cost when you own the home; Buyer beware.

2. The fact that you report that an oil tank was "abandoned" AND that it still contains oil tells me that the oil tank has not been properly abandoned. Doing so would have required removing the oil and any water in the tank, checking for leaks, and if tests found no leak evidence, filling the tank with sand in place, or removing the tank;

3. If tests show that the tank leaked - perhaps below ground - the leak must be reported to your department of environment, the tank removed, and the leak -spill cleaned-up.

So it would make sense to have appropriate tests by an independent expert done before you buy the home.

Yes in some cases oil fumes can be ignited; I can't assess the risk in your case for a home I've not seen.

Question: heat gun could ignite heating oil fumes

(Aug 7, 2016) V Bakowsky said:

I am in the process of removing paint from some old cedar shingles on a side of my house using a heat gun.

My oil heating fuel pipes run through that area. I am a bit nervous getting too close to the pipes with my heat gun. I suspect that I am being overly cautious -

I really am giving them a wide berth. I haven't located any warnings about heat in and around these pipes on the internet. How cautious should I be?

Reply: Liquid No. 2 home heating oil will ignite at about 494 deg. F. or 256 deg C.

Liquid No. 2 home heating oil will ignite at about 494 deg. F. or 256 deg C. Your heat gun may produce temperatures well above that range.

But your oil fill and vent pipes do not normally contain oil. However I'd avoid significant-heat application to the piping itself because of the risks of causing a leaky joint and the (I suspect much more obscure and unlikely) risk of igniting oil vapors by a spark or open flame.

The flash point - the temperature at which a substance will ignite - for home heating oil fumes can be as low as 140 degF. - source: MSDS for No. 2 Home Heating oil, retrieved 2016/08/07, example original source: tsocorpsite.files.wordpress.com/2014/08/utility-fuel-oil.pdf

Also see these notes on oil fume exposure

inspectapedia.com/oiltanks/Fuel_Oil_Exposure_Limits.php

Question: explosion hazard from cutting an oil tank with a reciprocating saw?

2017/09/06 PC said:

Can I remove an oil tank by cutting it with a reciprocating saw? Is there an explosion hazard?

Reply: Risks of Explosion From Cutting Up an Old Steel Oil Tank?

Photograph of a modern oil storage tank listing label.PC

If the tank has been emptied and cleaned and contains NO combustible vapors you could cut it. Otherwise there is a low but not zero risk.

Certainly heating oil or oil tank removal companies do frequently cut-up old oil tanks to remove them, some using a saw, others a grinder, others a steel nibbling tool.

When an oil storage tank has not been cleaned thoroughly (which it won't have been considering the trouble and cost to do so), you can expect an oily sludgy mess spilling out when trying to cut the tank across its vertical dimension.

Using a steel nibbler device that can cut the tank will make the slice with less friction and spark risk than using a reciprocating saw or "sawzall". While some fellows say they do it, I would not try using a rotating cutting grinder disc as the spark shower would just make me too scared.

Keep in mind that depending on where you live you may need a permit to remove and dispose of an oil storage tank.

The cost for a metal nibbler tool that can cut an oil storage tank ranges from $100. U.S. for a hand-held unit that you will not enjoy trying to use on a big cutting project to about $125. for an air-powered Ingersoll Rand 325 psi air powered nibbler tool (works), to a Fein BLK 5.0 6 Gauge Nibbler that's over $2,500.

This tool is rated for cutting 12-gauge steel. Renting a powerful heavy-gauge steel nibbler tool that can handle the oil tank metal may be an option.

A typical modern residential storage tank steel is 14-gauge (2.0mm) to 12 gauge (2.3mm). Some older residential oil tank walls are thicker. See the oil tank label in our photo above.

The article above on this page notes that while home heating oil is not as easily ignited as more-explosive fuels like gasoline or gasoline or LP gas fumes, nevertheless,

Vapors [from home heating oil or other petroleum products] may be ignited rapidly when exposed to heat, spark, open flame or other source of ignition. When mixed with air and exposed to an ignition source, flammable vapors can burn in the open or explode in confined spaces.

 

Question:

(Nov 2, 2012) jayesh said:
i am working as a safety professional. before 50 days back there was explosion in furnace oil tank containg max 5 kl. Its storage capacity is 30 kl. heater is attached electrically. what is the main reason for explosion and man hole fled to 25 feets and fell down on terrace of boiler house.

Reply:

Jayesh:

I'm of course concerned and interested in learning more about the explosion you cite, and would appreciate being given specifics - if appropriate, use the CONTACT US link for email found at page top or bottom.

I think you are asking a question but I'm not quite clear.

Question:

(Nov 29, 2012) Monica said:
What if my landlord has a oil tank in the basement from a old heater and thefumes are being released into the home?

Reply:

Monica,

in ARTICLE INDEX given at CONTINUE READING in the article abovce see

HEATING OIL EXPOSURE HAZARDS, LIMITS

to read about this problem.

Question: I want to fence off to hide a oil storage tank

(June 8, 2015) Roger said:
Is there and regulation I should be aware of if I want to fence off to hide a oil storage tank at a domestic property?

Reply:

In the More Reading ARTICLE INDEX found near the end of this page you'll find an article series beginning at OIL TANK LEAK & ABANDONMENT REGULATIONS

But as your local officials have the final legal say, check with your building department too. Normally as long as the tank is accessible I'd not expect there to be an issue with screening it.


...

Continue reading at OIL TANK LEAKS & SMELLS or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

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OIL TANK SAFETY at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


Or see this

INDEX to RELATED ARTICLES: ARTICLE INDEX to HEATING OIL, OIL BURNERS, OIL FIRED HEATERS, OIL TANKS

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