Levels occupancy factor

An equilibrium factor of 0.35, derived from measurements made during the local surveys, has been assumed to typify conditions in UK dwellings. This value has been used to convert the average radon concentrations measured in the national survey to potential alpha-energy concentration of radon decay-products. On average, persons in the UK spend 75% of their time in their homes and 15% of their time elsewhere indoors (Brown, 1983). The occupancy factor of 0.75, together with an equilibrium factor of 0.35, results in an annual exposure of 1.3 10"5 J h m"3 (0.0037 Working Level Months,... 

Before standards for indoor exposure to radon can be formally established, work is necessary to determine whether remedies are feasible and what is likely to be involved. Meanwhile, the Royal Commission on Environmental Pollution (RCEP) in the UK has considered standards for indoor exposure to radon decay products (RCEP, 1984). For existing dwellings, the RCEP has recommended an action level of 25 mSv in a year and that priority should be given to devising effective remedial measures. An effective dose equivalent of 25 mSv per year is taken to correspond to an average radon concentration of about 900 Bq m 3 or an average radon decay-product concentration of about 120 mWL, with the assumption of an equilibrium factor of 0.5 and an occupancy factor of 0.83. 

Here Nc is the density of states in the conduction band, g the level degeneracy factor, n the carrier concentration in the band, A the activation energy of the level, Boltzmann s constant, and T the temperature. Now, in general, except at fairly low temperatures, the occupancy for shallow levels (with/ = /s) will be small, i.e., fs 1, and consequently... 

Adiabatic and Condon." Since the Condon approximation separates the electronic and the vibrational parts of the problem (see Section 10c), most of the papers using this approximation emphasize the latter aspect. Specifically, they analyze the so-called Franck-Condon overlap integrals [the (Xm X ) of Eq. (42)] and the occupancy factors of these vibrational levels. Such analyses include (1) the influence of mode type and/or number as well as... 

Fig. 11.3 Mutual orientations of azulene molecules in the layered structure shown on Fig. 11.2, at two levels of z coordinate z = 0 corresponds to the layer with blue color, z = 0.25 to the red one. A, B, and C stand for different orientations at respective levels, numbers indicate site occupation factors for each of the particular orientations...

Between the demarcation levels E and Ep, the occupation factor is determined by the rates of hole and electron capture and interfacial electron transfer between the states and the reducing agent ... 

In a study conducted by Erdogan (2013) in another region of Turkey, Konya, the concentration levels of radon in thermal water samples varied from 0.60 + 0.11 to 70.34 + 3.55 kBq/m3 in the spring and from 0.67 + 0.03 to 36.53 + 4.68 kBq/m3 in the summer. The calculated effective doses due to radon inhalation ranged between 0.09 and 10.13 nSv in spring and between 0.10 and 5.26 nSv in the summer, considering a radon equilibrium factor of 0.4, an indoor occupancy factor of 0.8 through an... 

A mechanism of spin-lattice and spin-spin relaxations was also worked out at the same time. The point is that the relative levels occupancy N" N, between which a transition occurs, is defined by the Boltzmann factor. The probability of transition between two levels is greater the larger the distance between them and, consequently, the more N" N differs from 1. In y-gamma resonance, the energy dilference is of the order of 10 eV, so the upper level is always nearly free and resonance absorption of quantum is nearly always possible. In NMR resonance, the difference E"—E is extraordinarily small and factor N"/N is close to 1. Under such conditions, the occupancy of both levels is the same and the probability of transition should be very small and, basically, paramagnetic resonance must not be observed. However, it turns out that another mechanism of removing the excitation from the upper level exists. 

One of the most critical factors is draft. Many people at low activity levels (seated/standing) are very sensitive to air velocities, and therefore draft is a very common cause for occupant complaints in ventilated and air-conditioned spaces. Fluctuations of the air velocity have a significant influence on a person s sensation of draft. The fluctuations may be ex-... 

Since incoming air may he as much as 11 K colder or 25 K warmer than the conditioned space, the object of the duct and grille system must be to distribute this air and mix it with the room air with the least discomfort to the occupants. The subjective feeling of discomfort will depend on the final temperature difference, the velocity, and the degree of activity, cold air being less acceptable than warm. Velocities at head level should be between 0.1 m/s and 0.45 m/s and comprehensive factors will be found in the CIBSE Guide, Table B3.1. 

BEIs apply to 8 hr exposures, five days a week. However, BEIs for altered working schedules can be extrapolated on pharmacokinetic and pharmacodynamic bases. BEIs should not be applied, either directly or through a conversion factor, to the determination of safe levels for non-occupational exposure to air and water pollutants, or food contaminants. The BEIs are not intended for use as a measure of adverse effects or for diagnosis of occupational illness. 

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