``` OSWERHCHAP Handbook of Chemical Hazard Analysis Procedures (Includes Computer Disk) 520 1989 NEPIS online BO 01/14/97 PDF single page tiff liquid materials vapor hazardous accident model hazard tank discharge container gas emergency planning one material spill pressure accidents rate temperature OSWERHCHAP HANDBOOK OF CHEMICAL HAZARD ANALYSIS PROCEDURES FEDERAL EMERGENCY MANAGEMENT AGENCY f i, U.S. DEPARTMENT OF TRANSPORTATION U.S. ENVIRONMENTAL PROTECTION AGENCY image: countPages += 1 if (countPages == 2) { var el = document.getElementById("rankTop") if (el) if (-1 == -1) el.innerText = "All" var el = document.getElementById("rankBot") if (el) if (-1 == -1) el.innerText = "All" } // var elementCount = document.all("rankStart").length // for (i=0; i i *. j {Cxpv} + {(100-C)xpa} Relative vapor density= *-—*•—— -—*—i v y lOOxpa Where C = saturated concentration of the chemical vapor in air in percent by volume. Benzene has a molecular weight of 78.1 and a maximum vapor concentration (more precisely referred to as its saturated vapor concentration) of 13 16% in air at 79°F. Use of these values in the above equation, together with the assumption of an air temperature of 79°F, provides a true relative vapor density value of 1.22 What this means is that the benzene-air mixture directly above a pool of benzene at the specified temperature is only 1 22 times heavier than air and not the 2.7 times suggested by the vapor density frequently reported in the literature for this substance Since this mixture will very quickly mix with additional air as it drifts away from the pool, it will rapidly approach the density of pure air and behave as if there were little or no difference in its density. In scientific terms, it will behave as a neutrally buoyant vapor-air mixture. If the relative vapor density of a substance under prevailing discharge conditions exceeds 1.5 (as a general rule of thumb), then vapors or gases may indeed behave as heavier-than-air (or negatively buoyant) mixtures for some distance from the source of discharge. Conversely, a relative vapor density significantly less than one suggests that a vapor-air mixture may be lighter than air (or positively buoyant). In determining or deciding whether any particular gas or vapor will be negatively, neutrally, or positively buoyant in air, it is also often necessary to consider the circumstances under which the substance may be released to the atmosphere For example, in situations in which a compressed liquefied gas is discharged from a container, particularly when in the liquid state, the resulting vapor cloud or plume may include a considerable amount of fine liquid droplets. Although the gas or vapor mixture with air may normally be positively or neutrally buoyant, the presence of these relatively heavy droplets (also referred to as aerosols) may cause the cloud or plume to behave initially in a negatively buoyant fashion. 2.7 SOLUBILITY IN WATER All of us have observed that sugar and salt dissolve in water and seem to disappear, that our favorite alcoholic beverage can be mixed freely with water-based mixers, and that the "fizz" in containers of soda pop, tonic, or beer is due to carbon dioxide gas that has been dissolved in the liquid In each case, the solid, liquid, or gas that has dissolved in water is said to be soluble in water. 2-13 image: countPages += 1 if (countPages == 2) { var el = document.getElementById("rankTop") if (el) if (-1 == -1) el.innerText = "All" var el = document.getElementById("rankBot") if (el) if (-1 == -1) el.innerText = "All" } // var elementCount = document.all("rankStart").length // for (i=0; i Boiling point greater than ambient T T near ambient T T greater than ambient T but less than boiling point T greater than boiling point and greater than ambient T Liquid at ambient T (6) Hot liquid (7) Hot or warm compressed gas or vapor over hot liquid (8) Boiling point less than ambient T T near ambient T T greater than boiling point and greater than ambient T Compressed gas or compressed liquefied gas under pressure at ambient T (9,10) Hot or warm compressed gas or com- pressed liquefied gas under pressure at T greater than ambient (9,10) Notes: T = temperature within container, ambient T = temperature outdoors image: countPages += 1 if (countPages == 2) { var el = document.getElementById("rankTop") if (el) if (-1 == -1) el.innerText = "All" var el = document.getElementById("rankBot") if (el) if (-1 == -1) el.innerText = "All" } // var elementCount = document.all("rankStart").length // for (i=0; i o a o o S 0 s •»s X CO Figure 3.3 Maximum Puff Concentration vs. Time or Distance 0% Time or Distance — 3-14 image: countPages += 1 if (countPages == 2) { var el = document.getElementById("rankTop") if (el) if (-1 == -1) el.innerText = "All" var el = document.getElementById("rankBot") if (el) if (-1 == -1) el.innerText = "All" } // var elementCount = document.all("rankStart").length // for (i=0; i" to represent this key on screen displays, the following text will refer to this key as the ENTER key • (Y or /N) ~ means that the program will accept either a "F1 or "y" followed by a press of the ENTER key, or simply a press of the ENTER key alone, to indicate a yes answer A "N" or "n" followed by a press of the ENTER key is required to indicate a no answer !*,„II • (Y/N or ) — means that the program will only accept "Y" or "y followed by a press of the ENTER key as meaning yes. A "N" or "n" followed by a press of the ENTER key, or simply a press of the ENTER key alone, indicates a no answer • (Y/N) -- means that entry of an upper or lower case "y" or "n" followed by a press of the ENTER key are the only acceptable responses The choice of which of these options appears at the end of every question was made on the basis of which answer is most likely to be provided by the user in any given situation Thus, although the program asks the user numerous questions during an accident scenario evaluation, a great many of them can be quickly answered by simply keeping the "little" finger of the tight hand close to the ENTER key on the keyboard Selection of Menu Options All primary menus in ARCHIE present a list of options with each line item preceded by a lower case letter. Selection of any specific option is accomplished by typing the appropnate letter (either lower or upper case letters are acceptable) and following the entry with a press of the ENTER key 12-7 image: countPages += 1 if (countPages == 2) { var el = document.getElementById("rankTop") if (el) if (-1 == -1) el.innerText = "All" var el = document.getElementById("rankBot") if (el) if (-1 == -1) el.innerText = "All" } // var elementCount = document.all("rankStart").length // for (i=0; i EXPLOSICN HAZAFD ABE CONTESTS FTAMfiPIE CONTAINER CVEBEEESSQRIZKnCN EXPLOSION HAZfiRD IGNmCNOF LIQUID DOWNWIND TOXIC GAS HAZARD DOWNWIND TOXIC VAPOR HAZARD FIREBALL OR BLEVE HAZARD VAPOR CLOUD FIRE HAZARD IF IGNITED JET HAZARD IF IGNITED VAPOR CLOUD FIRE HAZARD IF IGNITED D06«NWIND TOXEC VRPCRCRGAS HAZARD POOL FIRE HAZARD UPON IGNITION CF LIQUID EXPLOSION HAZARD IN SEWERS AND CONFINED SPACES VAPOR CLOUD EXPLOSION HAZARD IF IGNITED VAPOR CLOUD EXPLOSICN HAZARD IF IGNITED FIGURE 12.1 HP AfTTTV QPTT.T. HA7ARm image: countPages += 1 if (countPages == 2) { var el = document.getElementById("rankTop") if (el) if (-1 == -1) el.innerText = "All" var el = document.getElementById("rankBot") if (el) if (-1 == -1) el.innerText = "All" } // var elementCount = document.all("rankStart").length // for (i=0; i or = 4/8 Cloudiness** - E D D D < or = 3/8 Cloudness - F E D D S3 (J1 f* *Apphcable to heavy overcast conditions day or night **Degree of Cloudiness = Fraction of sky above horizon covered by clouds image: countPages += 1 if (countPages == 2) { var el = document.getElementById("rankTop") if (el) if (-1 == -1) el.innerText = "All" var el = document.getElementById("rankBot") if (el) if (-1 == -1) el.innerText = "All" } // var elementCount = document.all("rankStart").length // for (i=0; i