Plant Operator Selection System Test Plant Operator Selection System Tables and Graphs Interpretation 5

Question 1

A table shows safety incident rates per 100 employees over four quarters: Q1=3.2, Q2=2.8, Q3=3.0, Q4=2.4. What is the average quarterly incident rate?

Accepted Answer

2.85

Answer

Average = (3.2 + 2.8 + 3.0 + 2.4) / 4 = 11.4 / 4 = 2.85 incidents per 100 employees.

Question 2

A calibration table for a level transmitter shows: 4 mA = 0% level, 12 mA = 50% level, 20 mA = 100% level. If the transmitter reads 16 mA, what is the tank level?

Accepted Answer

75%

Answer

16 mA is 12 mA above the 4 mA baseline; 12/16 × 100 = 75% of the full 16 mA span.

Question 3

A comparison table shows cooling tower performance at different ambient temperatures. At 90°F ambient, the cooling capacity drops by 15% versus the rated capacity of 800 tons. What is the derated capacity?

Accepted Answer

680 tons

Answer

15% of 800 = 120 tons; derated capacity = 800 − 120 = 680 tons.

Question 4

A graph shows two process variables over time. Variable X reaches its peak 30 minutes before Variable Y reaches its peak. This time offset is called:

Accepted Answer

Lag

Answer

A time delay between cause and effect in process variables is known as lag (or process lag).

Question 5

A production yield table shows: Batch 1=94.2%, Batch 2=91.8%, Batch 3=95.5%, Batch 4=93.1%, Batch 5=90.4%. The plant target is 93%. How many batches met or exceeded the target?

Accepted Answer

3

Answer

Batches 1 (94.2%), 3 (95.5%), and 4 (93.1%) all meet or exceed the 93% target — that is 3 batches.

Plant Operator Selection System Test Practice Test

Plant Operator Selection System Test Practice Test

Plant Operator Selection System Test Plant Operator Selection System Tables and Graphs Interpretation 5