As the name implies, indoor air pollution deals with air contamination in enclosed spaces such as homes, offices, work areas, etc. Suppose that you are designing a ventilation system for a restaurant as shown in figure. The restaurant serving area consists of two square rooms and one elongated room. Room 1 and room 3 have sources of carbon monoxide from smokers and a faulty grill, respectively. Steady- state mass balances can be written for each room. For example, for the smoking section (room 1), the balance can be written as

0 = W_smoker + ? ?Q_?c_{?? ? ??} ? ?Q_?c₁? + ?E₁₃(c₃ ? c₁)

?(load) ?+ (inflow) ? (outflow) + (mixing)

Or substituting the parameters

225_c1 ? 25_c3 = 1400

Similar balances can be written for the other rooms.

(a) Solve for the steady-state concentration of carbon monoxide in each room.

(b) Determine what percent of the carbon monoxide in the kids? section is due to (i) the smokers, (ii) The grill, and (iii) The air in the intake vents.

(c) If the smoker and grill loads are increased to 2000 and 5000 mg/hr, respectively, use the matrix inverse to determine the increase in the concentration in the kids? section.

(d) How does the concentration in the kids? area change if a screen is constructed so that the mixing between areas 2 and 4 is decreased to 5 m³/hr?

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e- 150 m/hr Q = 100 m/hr O, 50 m/hr 25 m/hr (Kids' section) = 2 mg/m O. = 200 mhir =2 mg/m? 25 m/hr. 3 (Smoking section) Smoker load (1000 mg/hr) Grill load (2000 mig/hr 50 m/hr