Adjustment factors

E. N. Bamberger and co-workers, Eife Adjustment Factors forBall and Roller Bearings, American Society of Mechanical Engineers, New York, 1971. 

The above procedure produces blast parameters applicable to a completely symmetrical blast wave, such as would result from the explosion of a hemispherical vessel placed directly on the ground. In practice, vessels are either spherical or cylindrical, and placed at some height above the ground. This influences blast parameters. To adjust for these geometry effects, and 7 are multiplied by some adjustment factors derived from experiments with high-explosive charges of various shapes. 

TABLE 6.11b. Adjustment Factors for Spherical Vessels Slightly Elevated above Ground (Baker et al. 1975)... 

Figure 6.34. Adjustment factor for unequal mass fragments (Baker et al. 1983).

Models must be both realistic and also robust. A model which predicts effects which are quite contrary to common sense or to normal experience is unlikely to be met with confidence. To accord with this, some use of empirical adjustment factors in the model may be needed, in order to represent combinations of relatively unknown unknown factors. 

Using Table 6.11 a in Reference 5, divide Ps by an estimated (assume 0.03 geometry effects cause longer distances to the ps endpoint overpressure conditions. 

Since 4.3 > 3.5, the adjustment factor for Ps (1 psi) from Table 6.11a must be corrected. The proper value from the table is 1.4 ... 

Process Furaxce Cost, S - [Base cost (Fa + Fm + Fp)]index Pyrolysis or Reformer Fmice Cost, S. [Base cost (Fa + Fp)] index Adjustment factors... 

Exchanger Cost, - [Base cost (Fj + Fp) x F 1 Index Adjustment factors... 

A global Thomthwaite PET surface was calculated from the temperature surface data for a 0.5° resolution grid. The Thomthwaite method is known systematically to underestimate PET for dry conditions and to overestimate values for moist and cold environments. Consequently, an empirical adjustment factor was derived by CRU and applied to the data to bring the values closely in line with those of the Penman method. 

The price index is adjusted periodically according to an adjustment factor that is pre-established and exogenous to the company during the lifetime of the regulatory contract, but can be established on the basis of the fulfilment of certain policies by the company in the previous period (for example, R D policies, limits on spending on advertising and promotion and so on). 

The system is revised at intervals of several years, sometimes involving a general change in the products included and the adjustment factor. 

Table I. Risk Coefficient Adjustment Factors as a Function of Radon Daughter Disequilibrium...

Radon and Daughter Ratios Equilibrium Factor Adjustment Factor for Radon Daughter Risk Coefficient... 

To adjust for uncertainties in assessing potential cancer risks for short-term exposures under the multistage model, the 24-h exposure is divided by an adjustment factor of 6 (Crump and Howe 1984). 

This approach assumes that fe is known, the change in CL and k are proportional to CLcr, renal disease does not alter drug metabolism, any metabolites are inactive and nontoxic, the drug obeys first-order (linear) kinetic principles, and the drug is adequately described by a one-compartment model. The kinetic parameter/dosage adjustment factor (Q) can be calculated as ... 

Equation 3-21 can be modified for container vapors that are not saturated with the volatile. Let represent this adjustment factor then,... 

A recently pubhshed WHO/IPCS document regarding chemical-specific adjustment factors for interspecies differences and human variability (WHO/IPCS 2005) provides guidance for use of toxicokinetic data in dose-response assessment to develop the so-called Compound-Specific Assessment Factors (CSAFs) (Section 5.2.1.12). 

WHO/IPCS. 2005. Chemical-specific adjustment factors for interspecies differences and human variability Guidance document for use of data in dose/concentration-response assessment. Harmonization Project Document No. 2. http /whqlibdoc.who.int/publications/2005/9241546786 eng.pdf... 

The terminology within this area is not standardized. Other terms include safety factor, uncertainty factor, extrapolation factor, adjustment factor, and conversion factor. None... 

A is a calculated adjustment factor allowing for the differences in caloric requirement. 

It is also noted that there is overlap in the individual UFs and that the application of five UFs of ten for the chronic reference value (yielding a total UF of 100,000) is inappropriate. In fact, in cases where maximum uncertainty exists in all five areas, it is unlikely that the database is sufficient to derive a reference value. Uncertainty in four areas may also indicate that the database is insufficient to derive a reference value. In the case of the RfC, the maximum UF would be 3,000, whereas the maximum would be 10,000 for the RfD. This is because the derivation of RfCs and RfDs has evolved somewhat differently. The RfC methodology (US-EPA 1994) recommends dividing the interspecies UF in half, one-half (10° ) each for toxicokinetic and toxicodynamic considerations, and it includes a Dosimetric Adjustment Factor (D AF, represents a multiplicative factor used to adjust an observed exposure concentration in a particular laboratory species to an exposure concentration for humans that would be associated with the same delivered dose) to account for toxicokinetic differences in calculating the Human Equivalent Concentration (HEC), thus reducing the interspecies UF to 3 for toxicodynamic issues. RfDs, however, do not incorporate a DAF for deriving a Human Equivalent Dose (HED), and the interspecies UF of 10 is typically applied, see also Section 5.3.4. It is recommended to limit the total UF applied for any particular chemical to no more than 3000, for both RfDs and RfCs, and avoiding the derivation of a reference value that involves application of the full 10-fold UF in four or more areas of extrapolation. 

R] is the adjustment factor to account for anticipated differences in susceptibility between humans and the laboratory animals, i.e., to account for interspecies variabihty. The default value is 10, indicating that humans are much more susceptible. 

Qi 3] and [U] are adjustment factors to account for variations in the reliability of the database (data quality) and other sources of uncertainty in the data evaluation process. 

An aggregate adjustment factor of about 250 is typical the theoretical maximum value is... 

Application of a scientifically derived adjustment factor to the NOAEL, or LOAEL, of the critical effect established in the pivotal study. It is stated that if the database is inadequate, then human PNAELs cannot be derived scientifically. 

The scientifically derived adjustment factors include the following elements ... 

Interspecies differences (animal-to-human) mouse, a default value of 7 X 3 rat, a default value of 4 X 3 rabbit, a default value of 2.4 X 3 dog, a default value of 1.4 X 3. The first factor for each species is a calculated adjustment factor, allowing for differences in basal metabolic rate (proportional to the 0.75th power of body weight). The second factor of 3 is the assessment factor applied for remaining uncertainties (Section 5.3.3), for which the default value is 3. For local skin and respiratory tract effects, the assessment factor is 3, as adjustment for differences in body size is inappropriate. 

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