EEI MASS Test: Practice Tests & PDF Guides (2024)
Shlomik Silbiger

Shlomik, Mechanical Testing Expert at JobTestPrep.

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What is the MASS Test?

The MASS test is one of seven EEI tests. It was developed to serve as an employment selection test in the plant maintenance field. The MASS test is able to estimate the probability of a candidate's success in the following categories related to plant maintenance jobs:

  • Mechanic, machinist, electrician, welder, pipefitter, steel worker, rigger
  • Instrument and control repairer
  • Helper, painter, insulation worker

The MASS test is similar in design, scope and administration to the POSS test. It may also be used when selecting candidates for power plant maintenance positions in fossil, nuclear, and hydro plants.

MASS Test Battery

The MASS test battery is administered over approximately two hours. It consists of four tests (or sections):

  1. Mechanical Concepts (44 questions/20 minutes)
    This test assesses one's ability to understand mechanical principles. It consists of 44 multiple-choice questions, each one containing an illustration of a mechanical situation. This test is allotted 20 minutes.
  2. Assembling Objects (20 questions/15 minutes)
    This test assesses one's ability to visualize the properly assembled form of an object. A diagram featuring parts of an object is presented, each part labeled with a letter. Candidates are required to assemble the parts so that ones with corresponding letters are put together. The test consists of 20 multiple-choice questions and has a 15-minute time limit.
  3. Mathematical Usage (18 questions/7 minutes)
    This test assesses one's ability to work out basic mathematical problems using the information provided at the beginning of the test. The test includes 18 multiple-choice questions and must to be completed within seven minutes.
  4. Reading Comprehension (36 questions/30 minutes)
    This test assesses one's ability to read and comprehend written materials generally found in power plant training manuals. The test taker is presented with five passages and several follow-up, multiple-choice questions. The test includes 36 questions and must to be completed within 30 minutes.

MASS Test Practice Questions


MASS Mechanical Concepts Sample Question

Try answering this question in 27 seconds- that's how long you'll have during the test.

A tube is attached to the left hand side of a connector and another tube is connected to the opposite face. Water enters the system from the left tube, flows freely through the connector, and exits via the right hand tube. At which opening is the water velocity the greatest?

A. Opening 1
B. Opening 2
C. Impossible to tell
D. Same for both openings
Correct Answer
Incorrect Answer

The correct answer is 2.

Since the water flows freely from one side of the system to the other, at any given time the  amount of water entering the system is equal to the amount of water leaving it.

Q(in) = Q(out)

Where Q is the flux, which represents this amount of water and is measured in units of Volume/Time.

The flux is calculated as
A=Section Area[m^2]
V=Fluid Velocity[m/s]

If we compare the incoming flux with the outgoing flux we will see that since the cross-section of opening 2 is half the size of opening 1, the fluid velocity must be double in order to maintain a constant flow.

The mathematical calculation:

The speed at the exit (V2) is double the speed at the entrance (V1).

MASS Reading Comprehension Sample Question

Try answering this question in 50 seconds- that's how long you'll have during the test.

The most important and continually emerging factor for financial firms to operate successfully in extended global markets is their ability to efficiently serve discerning, highly sophisticated, better educated, and more powerful consumers addicted to the ease and speed of technology. Financial firms that do not realize the importance of these customer-oriented traits are wasting their resources and will eventually perish. Businesses that fail to recognize the impact of these consumer-driven transformations will struggle to survive or cease to exist in a newly forged global financial service community that has been forever changed by deregulation.

Companies should not perish if they recognize which of the following consumer traits?
A. Efficient
B. Perceptive
C. Financially restricted
D. Uneducated
Correct Answer
Incorrect Answer

The correct answer is B.

Answer (B) is the correct answer because the text mentions that the consumer is “discerning," meaning he is perceptive.
Answer (A) is incorrect because the trait “efficiency” is mentioned in the text in relation to the company, not the consumer. Answer (C) is incorrect because the text does not mention anything about the consumer’s financial situation. Answer (D) is incorrect because the text explicitly states the opposite—that the consumer is “better educated."

MASS Scoring

The scores from the four MASS aptitude tests are combined into a Cognitive Index Score. This score allows for potential employers to predict the probability of a successful job performance.

It's also important to note that there is no penalty for guessing or wrong answers.

Prepare Online for MASS

Even small improvements in your score can determine whether or not your potential employer will be impressed. JobTestPrep's MASS practice pack contains practice materials for all MASS test sections, with in-depth answer explanations, that act as a MASS test study guide. Learn more about our state of the art MASS practice tests by practicing now.

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