Potential Problems

While good organisational and administrative arrangements are necessary to ensure risk assessments are tmdertaken and implemented effectively, problems can arise which jeopardise the risk assessment process in particular and health and safety in general. These problems can arise in three major areas, bureaucracy, conflict, and loss of focus. 

This term has come to be used to describe what are felt to be tiie worst features of contemporary organisation and conjures up visions of overregulation, inflexible procedures, red tape, disinterest in the customer and accoxmtability to a faceless committee. However, Weber considers that bureaucracy has a crucial role in our society as the central element in any kind of large scale administration but in its most rational form depends upon rules, procedures and authority to achieve its control. He suggests it has the following characteristics  

Examples of the bureaucratic mind set are revealed by its response to audit. Many organisations audit themselves for safety. A typical audit will generate a list of non-conformances against internal, national or international standards. Success is measured by the division having few nonconformances. The focus of management then becomes one of how to 

Within any oiganisation, people have their own ideas about priorities for themselves and for the organisation which not infrequently conflict with the official view. Many of the individuals in an organisahon are likely to be subject to conflichng demands upon their time, energy and their principles not only in their work where they may play a number of roles but also in their private lives. Conflicts can arise within and between individuals, groups, departments and organisations. 

A side effect of conflict is stress which can occur whenever an individual is put in a position of having to attack or defend. As stress builds up so equanimity is eroded and the propensity to argue, disagree or openly oppose grows with the risk of an escalation of potential conflict. 

Our analysis of the ILIT response assumes that the operative rate constant, km [see Eq. (77)], is eflfectively constant during the course of the ILIT measurement. For a perfect step function the operative temperature would be constant at T = T + ATgq [see Eq. (78)]. However, the ILIT perturbation only approximates a step function. Even if the system is only reasonably tuned (see Fig. 5), the postperturbation change in the interfacial temperature will likely be much less than the typical maximum value of ATeq 5 K. The sensitivity of the rate constant to temperature is deduced from  

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The Soret effect is effectively a liquid junction potential produced by a temperature gradient in a homogeneous electrolyte. The activity coefiicients of ions are generally not identical consequently, a temperature gradient produces a driving force, which will be opposed by potential. The implications of the Soret effect in an ILIT perturbation were discussed by Smalley et al. [5], who showed that there is a linear relationship between the Soret potential, A Fsoret, and the temperature difference between the electrode surface and the bulk solution, AT, i.e.  

is assumed to be the volume subjected to an instantaneous change in temperature, AT. For that volume we can write [101]  

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While Eq. III-18 has been verified for small droplets, attempts to do so for liquids in capillaries (where Rm is negative and there should be a pressure reduction) have led to startling discrepancies. Potential problems include the presence of impurities leached from the capillary walls and allowance for the film of adsorbed vapor that should be present (see Chapter X). There is room for another real effect arising from structural peiturbations in the liquid induced by the vicinity of the solid capillary wall (see Chapter VI). Fisher and Israelachvili [19] review much of the literature on the verification of the Kelvin equation and report confirmatory measurements for liquid bridges between crossed mica cylinders. The situation is similar to that of the meniscus in a capillary since Rm is negative some of their results are shown in Fig. III-3. Studies in capillaries have been reviewed by Melrose [20] who concludes that the Kelvin equation is obeyed for radii at least down to 1 fim. 

Slater P C and Koster G F 1954 Simplified LCAO method for the periodic potential problem Phys. Rev. 94 1498-524... 

Expanding Waves. As a further application we tmn to the expanding potential problem [261-263], where we shall work from the amplitude modulus to the phase. The time-dependent potential is of the form... 

In the work of King, Dupuis, and Rys [15,16], the mabix elements of the Coulomb interaction term in Gaussian basis set were evaluated by solving the differential equations satisfied by these matrix elements. Thus, the Coulomb matrix elements are expressed in the form of the Rys polynomials. The potential problem of this method is that to obtain the mabix elements of the higher derivatives of Coulomb interactions, we need to solve more complicated differential equations numerically. Great effort has to be taken to ensure that the differential equation solver can solve such differential equations stably, and to... 

Vgiec and Vxc represent the electron-nuclei, electron-electron and exchange-correlation dionals, respectively. The delta function is zero unless G = G, in which case it has lue of 1. There are two potential problems with the practical use of this equation for a croscopic lattice. First, the summation over G (a Fourier series) is in theory over an rite number of reciprocal lattice vectors. In addition, for a macroscropic lattice there effectively an infinite number of k points within the first Brillouin zone. Fortunately, e are practical solutions to both of these problems. 

One potential problem with this approach is that heat loss from a small scale column is much greater than from a larger diameter column. As a result, small columns tend to operate almost isotherm ally whereas in a large column the system is almost adiabatic. Since the temperature profile in general affects the concentration profile, the LUB may be underestimated unless great care is taken to ensure adiabatic operation of the experimental column. 

Some potential problems of alcohol fuels have been addressed by a dding small amounts of gasoline or specific hydrocarbons to the fuel, reducing the flammabihty envelope and providing luminosity in case of fine. 

Health and Safety Factors. The low solubiUty of calcium fluoride reduces the potential problem of fluoride-related toxicity. Water saturated with calcium fluoride has a fluoride concentration of 8.1 ppm as compared to the recommended water fluoridation level of 1 ppm fluoride ion. However, because the solubiUty of calcium fluoride ia stomach acid is higher, continued oral ingestion of calcium fluoride could produce symptoms of fluorosis. The adopted TWA limit for fluorides as F is 2.5 mg/m (68,69). 

In summary, the bad features of partial combustion processes are the cost of oxygen and the dilution of the cracked gases with combustion products. Flame stability is always a potential problem. These features are more than offset by the inherent simplicity of the operation, which is the reason that partial combustion is the predominant process for manufacturing acetylene from hydrocarbons. 

Solids. Proper handling and disposal techniques can obviate potential problems associated with the soHd waste-retorted shale. Retorted shale disposal and revegetation have posed no adverse environmental impacts at the Unocal Parachute Project (62). EarHer studies carried out using Paraho and Lurgi retorted shales indicated that these materials behave as low grade cements (63,64) and can be engineered and compacted into high density materials (Pig. 11) and water impervious stmctures (Table 15). 

A potential problem for rotary valve usage is that they tend to pull material preferentially from the upside of the valve, which can affect the mass flow pattern. Another problem is that once soHd drops from the vane, the air or gas that replaces it is often pumped back up into the bin. In addition, air can leak around the valve rotor. Such air flows can decrease the soflds flow rates and/or cause flooding problems. A vertical section shown in Figure 13 can alleviate the preferential flow problem because the flow channel expands in this area, usually opening up to the full outlet. To rectify the countercurrent air flow problem, a vent line helps to take the air away to a dust collector or at least back into the top of the bin. 

Because HCl is constandy present in most parts of the equipment, corrosion is always a potential problem. Chlorine and benzene, or any recycled material, must be free of water to trace amounts to prevent corrosion and deactivation of the catalyst. The reactor product contains HCl and iron. In some plants, the product is neutralized with aqueous NaOH before distillation. In others, it is handled in a suitably-designed distillation train, which includes a final residue from which FeCl can be removed with the high boiling tars. 

Several other antigens with good immunocontraceptive potential have been identified and investigated in laboratory animals. In most studies, the rate and duration of the immunocontraceptive effect are less than acceptable. A potential problem in immunological approaches to antifertUity research is the need for a safe, effective adjuvant and suitable animal models for evaluating the efficacy and safety of methods (111). Newer and more effective adjuvants are required for contraceptive vaccines and vaccines in general. 

Typically NO conversion ranges from 80 to 95% and there are corresponding decreases in CO and hydrocarbon concentrations. Potential problems associated with NSCR appHcations include catalyst poisoning by oil additives, such as phosphoms and 2inc, and inadequate control systems (37). 

High reliability. Many things can go wrong with a steam tracing system but, very few of the potential problems lead to a heat tracing failure. Steam traps fail, but they usually fail in the open position. 

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