Figure 16 - location of fixtures

The calculation of the required number of lamps finds by the formula

N_св=S_n/l_c² (5.4)

Where, Sn - The illuminating the room;

N_св = 6 * 3/4, 79 = 3,76 ≈ 4

Used the method of utilization of luminous flux:

i= ab/( h_p(a+b)) (5.5)

where, i - Index of premises;

a, b, hp - length, width, height of the room;

Our i = 6 * 3 / (0.8 * (6 +3)) = 2.5.

The coefficient of uneven lighting for fluorescent lamps z = 1.1. The safety factor for media containing less than 1mg/m³ dust and smoke, provided cleaning fixtures at least 4 times a year kz = 1.8

The reflection coefficient of the ceiling P = 0.5

Wall reflectance Pc = 0.3

The coefficient of luminous flux at a given index premises and reflection coefficients of the walls and ceiling ŋ = 0.48

Number of lamps:

N = (E * S_{n *} z *kz)/(Fl * N_св * ŋ) (5.6)

N = (500 * 18 * 1.1 * 1.5) / (2200 * 4 * 0.48) = 14850/4224 = 3.52

5.7.1 Calculation of the total noise

In the laboratory "NIT" 10 PCs and one server. The average noise level is 40 dB of single PC, a server 60dB. Objective: To determine the actual intensity of the sound sources to the levels of intensity and find the total noise level for all sources.

The actual intensity of sound determined by the formula

L = 10*lg(J/J₀) (5.7)

Where, J - the actual value of the power of sound, W/m2;

J₀ - the threshold values ​​of sound power, W m-2 (J0 = 10-12 W/m2);

lg - logarithm of the decimal.

L = 10 * lg (J/ J₀) = 10 * (lgJ - lg J₀) = 10 * lgJ - 10 * lg J₀ (5.8)

10 * lgJ = L + 10 * lg J₀ (5.9)

lgJ = L/10 + lg J₀ (5.10)

PC lgJ = 40/10 + lg10-12 = 4 - 12 = -8 W/m2

For the server lgJ = 60/10 + lg10-12 = 6 - 12 = -6 W/m2

The actual sound intensity for each PC -8 W m-2, the actual intensity of the sound server - 6 W/m2

The total noise from several sources with the same level of sound intensity or sound pressure L1 (dB) can be determined from

L = L₁ + 10lgn (5.11)

Where, n - the number of noise sources;

L₁ - a source of noise, dB

L = 40 + 10lg10 = 40 + 10 = 50 dB

The noise level from all of the computers is 50 dB.

To determine the total noise level using a formula

L = L_b + ∆ (5.12)

Where L_b - the larger of the folding noise sources dB.

Δ - «additive" at addition levels from two sources dB

L1 - L2 = 60 - 50 = 10dB (5.13)

If the noise is 10dB difference, Δ = 0,45

L = L_b + Δ = 60 + 0.45 = 60.45 dB (5.14)

The total noise level in the laboratory "NIT" is 60.45 dB. This is the optimal level of noise exceeds the laboratory.

5.7.2 Anthropogenic impact of the object on the environment and measures for environmental safety

In the laboratory "NIT" is nothing harmful to the environment. But the production of PCs may make changes in the ecology of the environment. Hazardous waste production is available on any industrial enterprise. This hire and stamping and sheet bending processes in the production cycle of computer technology. It is characterized as waste metal chips and scale, using water cycle industrial water cooled, using alkali and oils emulsions, gas emission from the heating furnaces. Modern automatic production of metal products has high environmental performance. It all depends on the enterprise, how it is prepared to go to meet nature. Enterprises using modern technology and environmentally friendly production with a certificate of ISO 14001 inflict minimal damage to nature.