Document YDYkOn7Qomx5N7MxXpN4jnv6V

bcc : USB/mj/RD/SS **>. mug - upxwft M. McEwen - MMCEW March 20, 1968 Mr. C. R. HI 1 liar Chemical Technology aranoh Atomic Energy of Canada Ltd. Plnawa, Manitoba, Canada Dear Mr. miller: Via at Monaanto war# plaaaad to have you aa our guast February 23. In reply to the four questions relating to auto-lgnltlon temper ature, we offer the following oomnentsi 1. Monaanto does not have a specific written requirement or operating code for prooeas temperatures to be lower than the AIT of materials processed, regardless of the technique used to determine AIT. We do, however, face eaoh physical characteristic of the material processed from the requirement of the process and talcs precautions deemed necessary to protect life and property. For example. If the process requires a material to be held above Its flash point In a tank, we provide Inert atmosphere to protect against flash fire. 2. We do process benzene far above Its AIT In tha manu facture of biphenyl. The AIT of benzene is listed between 990* and 1070*F., and the processing temper ature is between 1300* and 1400*F. Occasionally a failure oceurs and spontaneous Ignition takes placej out personnel are protested by fire walls, and the benzene supply Is valved off to allow fire to bum out. vr c <0 o TOWOLDMONOQ56570 Nr. C. R. Miller Pag* Two March 28, 1968 3. w* do have other manufacturing processes where An of some chemicals la axaaadad by process temperatures. Thaaa appaar in our petroleum and hydrocarbon manu faoturing oparatlona. for example, ona operation combines methane abora lta An of 1170*. with oxygen, but Ignition doaa not oeour baeauaa raaldanaa time la lass than that required for Ignition, Thara ara about nlna dlffarant taats for determining An, and thaaa ara highly smpirlcal and vary aenaltlva to technique. a wlda variation of results exists with thaaa nlna taats baeauaa of hasting rates and lnduetlon tinea to effect ignition. I an advised that differences of 150*f. ara reported for An of the sane ohaaieal baeauaa of differences In the various teat techniques. 4. I have attaohed the texts of latters fro* two major industrial insurance companies concerning the ACT of hydrogenated terphanyl. we do not have speeiflo information froe Underwriters' Laboratories at this time on the subject of An. I trust the above information will satisfy your requirements. It la our pleasure to be of servloe, and if we can be of further assistance, please call, dive my regards to Stan Hatoher. Vary truly youre. DXKllh Attachment aei Nr. S. R. Hatehar Atomic Inergy of Canada Ltd. Donald X. Xoush Knglneerlng Speoiallst functional fluids 00b7b7b "Reply to your letter has been delayed by the press of other work and the writer's absence from his office. "We would be of the opinion that for most of the situations in highly protected risk locations, the auto Ignition temperature of a heat transfer fluid would not be of great concern to the fire protection engineer. In most situations of course, direct fired furnaces offer temperatures high enough to ignite most any material. In other situations it would be anticipated that the heat transfer material would be contained mostly in closed equipment. "We do not have readily available information as to how authorities around the country might act on the subject. I would suggest that your Mr. of your corporate safety department and at your address might have this material available to you. If you have not already contacted that group I suggest you do." "Answering your letter, I can find no reason to object to the use of your heat transfer fluid HB-40. This is, of course, provided It is recognized by the user that the material is combustible and that the use is such that a non-flammable fluid is not required. "Actually, heat transfer oils used to be of the paraffinic type. These oils had a relatively high flash point, but had low auto ignition temperature because of their tendency to crack when exposed to air. The best heat transfer oils available from the oil refining industry have been those of a highly naphthenic character and their autoignition temperatures run around 725F. Cm that basis, the 705F. AIT of your oil would put it in the same general class. It would appear that the material you are proposing to market would be less subject to sludge formation and other troubles than the naphthenic oils now in general use. On that basis, we would be glad to sacrifice 20 in the AIT to obtain more trouble-free service. 006762?