Hash ignition

The heat transfer section of a plant was filled with oil after maintenance by opening a vent at the highest point and pumping oil into the system until it overflowed out of the vent. The overflow should have been collected in a bucket, but sometimes a bucket was not used, or the bucket was overfilled. Nobody worried about small spillages because the Hash point of the oil was above ambient temperature and its boiling point and auto-ignition temperature were both above 300°C. 

Other important properties include Hash point, volatility, viscosity, specific gravity, cloud point, pour point, and smoke point. Most of these properties are related directly to the boiling range of the kerosene and are not independently variable. The flash point, an index of fire hazard, measures the readiness of a fuel to ignite when exposed to a flame. It is usually mandated by law or government regulation to be 120° or 130° F (48° or 72° C), Volatility, as measured... 

Hash point measurements from the closed-cup method are quoted unless only data from the open-cup (oc) method are available. Data from Stephenson, R. M., Flash Points of Organic and Organometallic Compounds (New York Elsevier, 1987) Bond, J., Sources of Ignition (Oxford Butterworth, 1991). 

The hash point of a diesel fuel is the temperature to which the fuel must be heated to produce an ignitable vapor-air mixture above the hquid fuel when exposed to an open hame. The hash point test is a guide to the hre hazard associated with the use of the fuel and can be determined by several test methods, but the results are not always strictly comparable. 

Flammable gas vapor pressure 910 torr being heavier than air, it can travel a considerable distance to a source of ignition and Hash back autoignition temperature 429° C (804°F) fire-extinguishing measure stop the fiow of gas use a water spray to keep the surrounding area and fire- exposed containers cool. Butadiene vapors may polymerize and block the vents (NFPA 1997). 

The smoke, fire, and Hash points of a fatty material are measures of its thermal stability when heated in contact with air. The smoke point is the temperature at which smoking is first detected in a laboratory apparatus protected from drafts. The flash point is the temperature at which the volatile products are evolved at a rate sufficient to be ignited, but not to support combustion. The fire point is the temperature at which the volatile products support continued combustion. 

Liquids and solids that can be ignited under almost all ambient temperature conditions (e.g., gasoline). Hash point between 23°C (73°F)and38°C(100 F)... 

Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur (e.g., diesel fuel). Hash point between 38°C (100°F) and 93°C (200°F)... 

BP = Boiling Point FP = Hash Point IT = Ignition Temp... 

Ignition Temperature, Hash Point, Fire Point, and Smoke Point... 

Coupound Formula Mole- cular Wdght Mdting Point rn Botllng Point Cf) Hash Point CF) Ignition Temp. CP)... 

Polymethylene Polyphenyl Isocyanate — Rre Hazards Hash Point (deg. F) 425 OC Flammable Limits in Air (%) Not pertinent Fire Extinguishing Agents Dry chemical or carbon dioxide Fire Extinguishing Agents Not to be Used Not pertinent Special Hazards of Combustion Products Not pertinent Behavior in Rre Containers may explode Ignition Temperature (deg. F) Data not available Elearical... 

Vapors may travel to a source of ignition and Hash back. Container may explode in heat of fire. 

Above Hash point, vapor-air mixtures are explosive within ftammable linuts noted above. Vapors can ftow along surfaces to distant ignition source and flash back. Contact with strong oxidizers may cause fire. Sealed containers may rupture when heated. This material may produce a floating fire hazard. Sensitive to static discharge. 

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