A chemical plant, CMM Chemical Sdn Bhd located in Pasir Gudang is the country's leading manufacturer of chlorine, caustic soda, hydrochloric acid and sodium hypochlorite. The chemicals were manufactured in two different plants. Plant A produces chlorine and caustic soda, while Plant B produces hydrochloric acid and sodium hypochlorite. The company adhere to the highest safety standards in all work practices and ensure the protection of the staff. The safety officer was assigned to develop a simple assessment that can help employers to control and monitor chemical exposure toward the employees and meet the legal requirements.

The workers worked for an $8-$hour shift per plant per day. They were exposed to the different type of chemicals based on their working shift at the respective plant as shown in Table $2\mathrm{.}1.$

Table $2\mathrm{.}1$: PEL for each chemical

$\backslash$table$[[$Plant$,$Chemicals,$\backslash$table$[[$Permissible exposure limit$],[($PEL$),$ ppm$]]],[$A$,$Chlorine,$1],[,$Caustic soda,$2000],[$B$,$Hydrochloric acid,$5],[$Sodium hypochlorite,$1]]$

The health risk of the workers can be estimated using the combined exposure index $($CEI$)$ as shown in $Eq(1).$

CEI$=\frac{C_1}{PE{L}_1}+\frac{C_2}{PE{L}_2}$

where $C$ is the concentration in the air of the chemical with subscript $1$ and $2$ to represent $2$ chemicals. If CEI exceeding value $1$ means the worker are overexposed to the chemicals and appropriate action need to be done to maintain a good health of workers.

Formulate algorithm and flowchart of decisional structures to compute the combined exposure index $($CEI$)$ for each worker based on shift and the given concentration of the respective

$1$

chemicals. Design an algorithm and flowchart that returns CEI value and appropriate message if CEI less than $1,$ and warning message if CEI exceeding $1.$ Samples of the expected output are shown in Figure $2\mathrm{.}1.$

Command Window

$,$Worker ID$=2401$

$,$Please select plant $(\frac{A}{B})=A$

$,$Exposed concentration chlorine $($ppm$)=0\mathrm{.}5$

$,$Exposed concentration caustic soda $($ppm$)=600$

$,$The combine exposure index: $0\mathrm{.}8$

$,$The exposure is within an acceptable limit

$fx>>$

Command Window

$,$Worker ID $=3411$

$,$Please select plant $(\frac{A}{B})=B$

$,$Exposed concentration hydrochloric acid $(ppm)=4\mathrm{.}5$

$,$Exposed concentration sodium hypochlorite $(ppm)=0\mathrm{.}9$

$,$The combine exposure index: $1\mathrm{.}8$

$,$The exposure is exceeding the limit$.$ An immediate action needs to be taken!

$fx>$