hazardous area classification for diesel oil storage tankfarm
hazardous area classification for diesel oil storage tankfarm
(OP)
As the flash point of diesel oil (or even fuel oil) is above 65 deg.C most of the people consider the diesel oil storage tank farm as non-hazardous area when preparing the Hazardous Area Classification drawing. Another argument also is: as the auto ignition temperature is very high, 257 deg.C, most of the time the storage tank farms are classified as non-hazardous area. Recently there are some arguments on this subject.
Any one who could contribute on this subject?
Would appreciate very much for your valuable comments urgently.
Any one who could contribute on this subject?
Would appreciate very much for your valuable comments urgently.





RE: hazardous area classification for diesel oil storage tankfarm
RE: hazardous area classification for diesel oil storage tankfarm
RE: hazardous area classification for diesel oil storage tankfarm
The applicable Codes in this case are "NFPA 70 (i.e NEC Chapter 5)" and "IP model Code Of Safety Part 15 (latest edition)". This is not a military installation. It is an "Oil Storage Terminal Project".
The Owner demanded to be classified the TankFarm as hazardous area whereby Contractor put up the area classification as "Safe" area. Thus there is a dispute on the subject.
Once the "NFPA 70" is specificed, it also refers back to "NFPA 30". Even API RP 500 is also more or less the same as "NFPA 70".
The argument is that under the normal atm. pressure and temperature, Diesel Oil does not produce flammable gas (NOTE: Diesel Storage is under atm. Pressure). Remember in Diesel Engine, in order to achieve combustion you need a compression stroke. In some Diesel Engine they also provide heater to preheat before engine is started. Thus there is no flammable gas around at atm temp. and pressure, thus no hazardous area (safe area).
Another argument also is the auto ignition temperature is 257 deg.C. Thus as long as there is no naked flame (keep the nake flame away)and heat producing equipment away from the TankFarm, it can be a "Safe Area". It all depends on the Plant Layout Design.
Thus in conclusion the TankFarm can be classified as "safe Area" provided the design met the above arguments.
Anybody who disagree on these arguments??
Welcome all further comments!
RE: hazardous area classification for diesel oil storage tankfarm
RE: hazardous area classification for diesel oil storage tankfarm
Hope this helps
RE: hazardous area classification for diesel oil storage tankfarm
“Refer to NFPA 325 for properties of specific flammable liquids, flammable gases, and volatile solids. Flammable and combustible liquids vary in volatility and are defined in NFPA 30.” … … “Combustible (Class II and Class III) liquids, such as kerosene and diesel fuel, are defined as liquids having a closed cup flash point at or above 373°C (100"F), as determined by the test procedures and apparatus described in NFPA 30.”
NFPA 497 does not list Diesel but lists fuel oil. Diesel may be called number 2 fuel oil where kerosine is number 1 fuel oil.
Diesel is generally unclassified. However, fuel oil will burn easily if agitated or otherwise atomized. Use good sense.
John