Perhaps we must all go back to the beginning. If a flammable solvent is miscible with water, and, if a flash point can be developed following one of the test measures specified in Section 1.7.4 of NFPA 30, then the solvent must be handled & stored in accordance with NFPA 30, OSHA, EPA, etc. regardless of opinions of others. So, when one is taking a known flammable and mixing it with water and creating a mixture, one must treat (handle & store) the mixture as flammable, unless the researcher has tested all samples fully in accordance with ASTM standards, the mixture must be treated as flammable, due to a lack of scientifically justified data. Regarding Test Methods. NFPA Section 1.74 states: 1.7.4 Determination of Flash Point. The flash point of a liquid shall be determined according to the methods specified in this subsection. 1.7.4.1 The flash point of a liquid having a viscosity below 5.5 centiStokes at 40°C (104°F) or below 9.5 centiStokes at 25°C (77°F) shall be determined in accordance with ASTM D 56, Standard Method of Test for Flash Point by the Tag Closed Cup Tester. Exception: Cut-back asphalts, liquids that tend to form a surface film, and liquids that contain suspended solids shall not be tested in accordance with ASTM D 56, even if they otherwise meet the viscosity criteria. 1.7.4.2 The flash point of a liquid having a viscosity of 5.5 centiStokes or more at 40°C (104°F) or 9.5 centiStokes or more at 25°C (77°F) or a flash point of 93.4°C (200°F) or higher shall be determined in accordance with ASTM D 93, Standard Test Methods for Flash Point by the Pensky-Martens Closed Tester. 1.7.4.3 As an alternative, ASTM D 3278, Standard Method of Tests for Flash Point of Liquids by Setaflash Closed Tester, shall be permitted to be used for paints, enamels, lacquers, varnishes, and related products and their components that have flash points between 0°C (32°F) and 110°C (230°F) and viscosities below 150 Stokes at 25°C (77°F). 1.7.4.4 As an alternative, ASTM D 3828, Standard Test Methods for Flash Point by Small Scale Closed Tester, shall be permitted to be used for materials other than those for which ASTM D 3278, Standard Method of Tests for Flash Point of Liquids by Setaflash Closed Tester, is specifically required. Sincerely, Alan P. McCartney CSP CHCM EMT-P Senior Technical Specialist - Property Agency Markets Loss Prevention Liberty Mutual Agency Markets 62 Maple Avenue Keene, New Hampshire 03431 (603) 358-4560 (603) 357-9595 (fax) alan.mccartney**At_Symbol_Here**libertymutual.com Helping People Live Safer More Secure Lives Former Fire Marshal - Concord (NH) Fire Dept Former Fire/Safety Analyst - Phillips 66 Chemical Company -----Original Message----- ------------------------------ Date: Tue, 30 Jan 2007 09:00:43 -0500 From: ErikaSubject: Re: Aqueous/Flammable solvent mixtures While I agree with Carl that flammable solvent mixtures are generally judged by their flash point, I disagree with the blanket statement that "All flammable solvents mixed with water should be treated, handled, and stored as flammable liquids." If a flammable solvent is completely miscible with water, said solution is used a dilution which yields no flash point, and the solution will not sustain combustion in a fire (i.e., has no "fire point"), no regulation or insurer is going to be concerned with their storage (or shipment) as a flammable liquid. The basic problem (to which Susan Hadden alludes) is generating the data for any such solution. Perhaps somebody has done this, but I am not aware of any published data. Richard Rosera Environmental Specialist Reckitt Benckiser, Inc. Hillsborough, NJ ----- Original Message ----- From: "Carl Zipfel" To: Sent: Monday, January 29, 2007 6:38 PM Subject: Re: [DCHAS-L] Aqueous/Flammable solvent mixtures > I went down this road many years ago and gave up. The problem is that the > only acceptable test of flammability is the "flash point". The flash point > defines flammability, and is what is accepted by the EPA, OSHA, and more > importantly the insurance companies. While the solvents that you mention > are miscible, once a little heat is applied they will separate and form a > flammable mixture in the air. All flammable solvents mixed with water should > be treated, handled, and stored as flammable liquids. > > Carl Zipfel, csp > > > ----- Original Message ----- > From: "Hadden, Susan [PRDUS]" > To: > Sent: Monday, January 29, 2007 2:36 PM > Subject: [DCHAS-L] Aqueous/Flammable solvent mixtures > > > > Many of our researchers use aqueous mixtures of miscible flammable > solvents > > for their LC work. They often have questions about storage and whether to > > treat them as flammable or not. I've been looking for data that might show > > me flammability as a function of concentration for the common solvents > such > > as CH3CN, MeOH, EtOH, IPA, etc. I've checked OSHA, NFPA and ASTM but can't > > find any solvent specific data. Does anyone know where I might find that > > information? > > > > Thanks, > > > > Susan Hadden > > Senior Occupational Safety Specialist > > J&J PRD Environmental, Health & Safety > > 1000 Rt 202, PO Box 300 > > Raritan, NJ 08869 > > 908-704-4295 (ph), 908-707-9211 (fax) > ------------------------------ Date: Tue, 30 Jan 2007 09:40:21 -0500 From: Dan Crowl Subject: Re: Aqueous/Flammable solvent mixtures Folks, I have done extensive experimental testing on both the flashpoints of solutions and also experimental characterization of the vapor above aqueous solutions. Aqueous solutions are complicated by non-ideal behavior. Clearly, if the solution is ideal, then the addition of water will increase the flashpoint temperature, reducing the hazard. However, if the solution is non-ideal, this may not be true. If the solution forms a minimum boiling point azeotrope, then the addition of water will REDUCE the flashpoint temperature and increase the hazard. Thus, by adding water the flammability hazard is increased! This is completely opposite of what one would expect! This is true also of other non-aqueous solutions that form minimum boiling point azeotropes. Common practice is to assume that the flashpoint of the mixture will be no lower than the lowest flashpoint of any of the pure components. This is not true with minimum boiling point azeotropes. To do a proper assessment, one would need to know if the solution forms a minimum boiling point azeotrope with water. This requires VLE data which is not commonly available. I have experimental flashpoint data on the following systems: Isobutanol - toluene - min. boiling pt azeotrope Secbutanol - water - max. boiling pt. azeotrope - flashpoint increases Ethanol - heptane - min. boiling az. Methanol - octane - min. boiling az. Ethanol - octane - min. boiling pt. az. Thus, it depends on a case by case basis and no general statements can be made. Dan Crowl Professor Department of Chemical Engineering Michigan Tech University crowl**At_Symbol_Here**mtu.edu ------------------------------ Date: Tue, 30 Jan 2007 10:24:50 -0600 From: Diane Amell Subject: Re: Aqueous/Flammable solvent mixtures If it is actual data that you want, I do have a chart and a graph showing the flashpoints of different concentrations in water. The source is the now-defunct NFPA 325 (although the information appears to be in NFPA's Fire Protection Guide to Hazardous Materials. (Being in the Upper Midwest, we have a lot of ethanol plants.) - Diane Amell, MNOSHA ----------------------------- Date: Tue, 30 Jan 2007 09:09:54 -0800 From: "Latimer, Lee" Subject: Re: Aqueous/Flammable solvent mixtures Dan, Do you have data on water mixtures with acetone, ethanol, methanol, dioxane, THF and other common water-miscible flammable solvents waste handlers will encounter? Lee Latimer -----Original Message----- Thank you for your co-operation. ******************************************************** ------------------------------ Date: Tue, 30 Jan 2007 20:43:15 GMT From: "paracelcusbombastusvon**At_Symbol_Here**juno.com" Subject: Re: Aqueous/Flammable solvent mixtures While as scientists we all love to investigate those little nuances of flash point vs concentration curves, etc, the real crux is what Erika only touched on -- INSURERS!!! It has been my experience in industry that an insurer does not care what the concentration of a flammable solvent is in water (or any toxic as0far-as that goes) only that you are using a flammable solvent. Therefore prepare for the worst case scenario. Lynn K
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