Safe distance

Andreev Belyaev (i960), 365-67 (Calcn and exptl detn of distances "safe to deton by influence thru air) 25) M. Sultanoff et al, "Shock Induced Sympathetic Detonations in Solid Explosives , pp 520-32 in Vol 2 of the 3rdONRSympDeton (I960)... 

The purpose of the well completion is to provide a safe conduit for fluid flow from the reservoir to the flowline. The perforations in the casing are typically achieved by running a perforating gun into the well on electrical wireline. The gun is loaded with a charge which, when detonated, fires a high velocity jet through the casing and on into the formation for a distance of around 15-30 cm. In this way communication between the wellbore and the reservoir is established. Wells are commonly perforated after the completion has been installed and pressure tested. 

With the reference block method the distance law of a model reflector is established experimentally prior to each ultrasonic test. The reference reflectors, mostly bore holes, are drilled into the reference block at different distances, e.g. ASME block. Prior to the test, the reference reflectors are scanned, and their maximised echo amplitudes are marked on the screen of the flaw detector. Finally all amplitude points are connected by a curve. This Distance Amplitude Curve (DAC) serves as the registration level and exactly shows the amplitude-over-distance behaviour" of the reference reflector for the probe in use. Also the individual characteristics of the material are automatically considered. However, this curve may only be applied for defect evaluation, in case the reference block and the test object are made of the same material and have undergone the same heat treatment. As with the DGS-Method, the value of any defect evaluation does not consider the shape and orientation of the defect. The reference block method is safe and easy to apply, and the operator need not to have a deep understanding about the theory of distance laws. 

The liquid becomes progressively darker in colour, and then effervesces gently as ethylene is evolved. Allow the gas to escape from the delivery-tube in T for several minutes in order to sweep out the air in F and B. Now fill a test-tube with water, close it with the finger, and invert the tube in the water in T over the delivery-tube so that a sample of the gas collects in the tube. Close the tube again with the finger, and then light the gas at a Bunsen burner at a safe distance from the apparatus. If the tube contains pure ethylene, the latter burns with a clear pale blue (almost invisible) flame if the ethylene still contains air, the mixture in the test-tube ignites with a sharp report. Allow the... 

Launched ia 1959, N. A. Savannah operated very weU. Starting ia 1962, it made a goodwill voyage around the world. It was able to travel a distance of several times the earth s circumference on one fuel loading. However, the ship was not competitive economically with oil-powered merchant ships. The shielding was quite adequate, so that the reactor was safe. Nonetheless the vessel was opposed by antinuclear groups and the N.A. Savannah was eventually retired and put on display ia Charleston, South Carolina. In 1994, the ship was transferred to Norfolk, Virginia, to be held ia reserve. 

The way the equipment is located on the background is based on the process flow sequence. Again, certain equipment such as fired heaters can be situated first to put them at a safe distance from other equipment. Other large equipment may have to be located where the soH-beariag load is best. 

SpiHs can also be diluted with large volumes of water. Care should be taken, however, because chlorosulfuric acid reacts violentiy with water Hberating heat, hydrochloric acid, and sulfuric acid mists and steam. The water should be appHed from a safe distance upwind of the spiH using a fog no22le. Remaining traces of acid should be neutrali2ed with soda ash, caustic soda, or lime before disposal. 

Another important issue in layout is the provision of safe access to equipment for emergency response needs such as fire-fighting etc. The layout also needs to provide for safe escape and rescue routes. As far as off-site population is concerned, the most important siting factor is the distance between the process... 

Provide safe separation distances for normal operation, maintenance, emergency egress, ergonomics... 

Ignition of flammable Provide safe separation distances release resulting in fire. Develop appropriate area electrical or explosion. classification Provide ignition source control Place ignition sources in positive pressure enclosure and buildings Provide adequate ventilation API RP500 BS 5345 BS 5958 NFPA-70 NFPA-77... 

Provide safe separation distances Install fixed fire protection and alarms, water sprays (deluge), and/or foam systems activated by flammable gas, flame, and/or smoke detection devices... 

To contain the temperature of the electrical circuits within safe limits for a particular temperature class of the surroundings, the maximum current rating for a minimum size of a conductor is also stipulated in ICC 60079-1 I. The constructional requirements also stipulate the minimum clearances and creepage distances in air between the conducting parts of all the intrinsically safe L lectrical eirctiits. 

The longer the distance, /, the greater will be the severity of the oncoming wave which would reduce the protective margin of the arrester dangerously. Safe proteetive distances are normally worked out by the arrester manu-... 

It is presumed that the protective distance (distance of the protected equipment from the arrester) is short and within safe limits. It too must be checked before a final selection of the arrester, as explained in Section 18.6.2. The above selection, however, seems to be appropriate for a distance up to 8-10 m as considered in Example 18.4. 

The use of corrosion-resistant materials and the application of corrosion protection measures are in many cases the reason that industrial plants and structures can be built at all. This is particularly so in pipeline technology. Without cathodic protection and without suitable coating as a precondition for the efficiency of cathodic protection, long-distance transport of oil and gas under high pressures would not be possible. Furthermore, anodic protection was the only protective measure to make possible the safe operation of alkali solution evaporators (see Section 21.5). 

Fig. 23-2 Safe distances from high-voltage overhead power lines.

Distances for storage of explosives Explosive and Toxic LLazard Materials page 370 (MeidI, 1970) Safe Handling Requirements during Explosive, Propellant and Pyrotechnic Manufacture (HSE, SIR 31)... 

Fire Hazards - Flash Point (deg. F) 2Q OC Flammable Limits in Air (%) 1.5 - 18.3 Fire Extinguishing Agents Dry chemical, alcohol foam, carbon dioxide Fire Extinguishing Agents Not To Be Used Water may be ineffective Special Hazards of Combustion Products No data Behavior in Fire Containers may explode in fires. Apply water to cool containers from a safe distance Ignition Temperature (deg. F) 959 Electrical Hazard No data Burning Rate No data. 

The drum is usually equipped with steam injection if required for winterizing or cold releases. Refer to Figure 7 for some of the details. If winterizing is necessary, then the steam should be temperature-controlled in order to maintain the seal water temperature at 4 to 10 C. It is important to note that the drum should be located at a minimum safe distance from the flare. 

Example security personnel Individuals who respond to releases in a defensive fashion and confine it from a distance Example firefighters, since they will respond to releases and process operators, since they may take defensive actions from a safe distance... 

FIGURE 9-11. These two workers appear to be looking on from a safe distance. They are both wearing level D protection with minor modifications. Photo courtesy of DuPont Tyvelfl Tychenfi protective apparel... 

Safe distance" (probability 0.95 no damage beyond this value), projectile limit,. nine damage to house ceilings llV . - wiralou broken... 

After the fire, the pump (and others) was relocated in the open air, under a canopy, so that small leaks would be dispersed by natural ventilation. It was surrounded by a steam curtain to disperse larger leaks. This would not have been necessary if the pump could have been located more than 150 m from sources of ignition. Gas detectors were installed to give early warning of any leaks. Emergency isolation valves (Section 7.2.1) were provided so that the pumps could be isolated safely from a distance [9]. What happened when another leak occurred is described in Section 7.2.1 (d). 

Remotely operated emergency isolation valves (see Section 7.2.1) should be fitted on filling lines. If the hose breaks for any reason, the flow can be stopped by pressing a button located at a safe distance. Reverse flow from the tank truck or car can be prevented by a check valve. 

In their research to determine safe stand-off distances between transportation routes and nuclear power plants, Eichler and Napadensky (1977) recognized that the... 

Taking into account the possibility of highly directional blast effects, Eichler and Napadensky (1977) recommend the use of a safe and conservative value for TNT equivalency, namely, between 20% and 40%, for the determination of safe standoff distances between transportation routes and nuclear power plants. This value is based on energy it should be applied to the total amount of hydrocarbon in the largest single, pressurized storage tank being transported. 

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