Question: From a human health perspective, small particulate matter ( PM ) can be harmful when inhaled. A large source for particles in your home is

From a human health perspective, small particulate matter (PM) can be harmful when inhaled. A
large source for particles in your home is food cooking and you will similarly see large emissions coming
from an outdoor BBQ. You decide to host a big BBQ party with some cooking indoors and some
outdoors. Your home is 250m3 and the air inside it is well mixed with an air exchange rate of 0.5hr-1.
Your stovetop preparations are emitting a steady 800ghr and your friends grilling outside are
producing a constant 10gm3 for PM that is entering the home. You know you want to keep the air
clean, so you also have a filter running inside that gives a first-order decay constant for PM of 0.48hr-1.
Assume that all of the following questions are coming after the system has reached steady state.
The parts to this question walk you through the steps of setting up and solving a mass balance problem as
demonstrated in class. Please apply this format (include all the steps shown in a-d) to all subsequent
problems involving mass balances for full credit. These steps will also be required on the exams.
a) Draw a box model corresponding to the problem statement above, labeling all mass fluxes into, out of,
and within the system boundaries.
b) Write the general mass balance equation for PM in the system you illustrated in (a), then explain which
(if any) terms can be cancelled.
c) Rearrange your equation from (b) to solve for the steady-state concentration of PM inside your home
in terms of variables -- no numbers yetII
d) Now use the values given in the problem statement to solve for the steady-state concentration of PM
inside your home (in gm3). Assume all of the PM from the smoke can be classified as PM ?25, which has a
National Ambient Air Quality Standard (NAAQS) of 12ugm3. Is the air you're breathing safe?
e) Now turn off the filter that is removing the particles at 0.48hr-1 first order decay. Calculate the new
steady-state concentration inside your home (in gm3). Are you safe? b) Write the general mass balance equation for PM in the system you illustrated in (a), then explain
which (if any) terms can be cancelled.
dMdt= INPUTS-OUTPUTS-filtration
Steady dMdt=0
0= Q_cook + C_outV-C_inV
I want to know if i am right for part b and need help with part E
From a human health perspective, small

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