TECH vs CAST vs MASS: Which EEI Test Is Yours?

The short answer: your job title decides it. EEI's catalog sends technician jobs that typically need an associate degree to TECH, construction and skilled-trade jobs (line work, facilities and equipment, meter service) to CAST, and power plant maintenance trades to MASS. All three include the same 44-question, 20-minute Mechanical Concepts test; the rest of each battery is different, and so is how much EEI publishes about it.

This page puts the three side by side, using EEI's own catalog and the brochures that LG&E and KU publish on its careers site. Where a brochure is silent, so are we.

Who each battery is for

Battery	Jobs, as EEI describes them
TECH	Technician jobs that typically require an associate degree — laboratory, environmental or chemistry technician; distribution planning technician; communications or telecommunications technician; drafter; estimator
CAST	Construction and skilled trades in three general areas: transmission and distribution; facilities and equipment; meter reader service and repair
MASS	Power plant maintenance positions — the brochure names mechanic, machinist, electrician, welder, pipefitter, steelworker and rigger

Employers add their own detail. LG&E and KU says it uses TECH for laboratory technicians, telecommunications, engineering design, drafting, GIS, and testing and relay technicians. Hawaiian Electric lists TECH alongside CAST, MASS and POSS among the EEI tests it uses. If your posting says "technician" and asks for an associate degree, TECH is the likely battery — but the posting, or your recruiter, has the last word.

What is in each one

Test	TECH	CAST	MASS
Mechanical Concepts	44 questions, 20 min	44 questions, 20 min	44 questions, 20 min
Arithmetic from drawings	Graphic Problem Solving — count and time not published	Graphic Arithmetic — 16 questions, 30 min	—
Reading for Comprehension	—	32 questions, 30 min	36 questions, 30 min
Mathematical Usage	—	18 questions, 7 min	18 questions, 7 min
Interpreting Diagrams	Count and time not published	—	—
Reasoning from Rules	Count and time not published	—	—
Assembling Objects	—	—	20 questions

Three things stand out. First, Mechanical Concepts is common to all three — the brochures describe it identically each time — so it is the best first investment whichever battery you face. Second, CAST and MASS publish counts and time limits for every section, while TECH publishes them for Mechanical Concepts only. Third, TECH is the only one of the three with no reading section and no math sprint; its other tests are about illustrations, diagrams and rules.

How long each sitting takes

All three brochures describe a sitting of about two hours. CAST's and MASS's timed sections add up to 87 and 72 minutes respectively, with the rest taken by instructions and administration. TECH's brochure describes two versions of the battery, each with the same four tests, and an administration time of approximately two hours, without breaking that down by test.

So if you read that a TECH section is "nine questions in nine minutes" or similar, be careful. Those figures match EEI's practice exercises, which are shorter than the real tests: Entergy tells applicants its practice tests are shorter than, and differ slightly from, the real tests. No brochure we have seen publishes them.

How each is scored

CAST's brochure describes a single index score from 1 to 10. MASS's says the component scores are combined into one index score translated into expected probabilities of successful job performance. TECH's says it may be machine- or hand-scored and that the scores on each test are combined into an Overall Score that predicts the candidate's likelihood of success in job performance. Neither the MASS nor the TECH brochure publishes a numeric range for that combined score.

None of the three publishes a cut score, and no employer publishes the level at which it hires. Our guide to EEI scores covers what is and is not known.

What to practise, by battery

• TECH: Mechanical Concepts at full length, then the three TECH-only question types — Graphic Problem Solving, Interpreting Diagrams and Reasoning from Rules. Our TECH practice covers all four and labels its own timings as ours wherever EEI has not published one.
• CAST: the four published sections, with special attention to the 7-minute math sprint and the drawing-based Graphic Arithmetic. See CAST practice.
• MASS: the same reading, mechanical and math work as CAST, plus Assembling Objects, which appears in no other battery we cover. See MASS practice.

If you genuinely do not know which you will sit, start with Mechanical Concepts. It is in all three, and in POSS and CAST-R too.

Can you be sent to more than one?

Yes, if you apply for jobs in different families — each job family has its own battery. Some utilities also combine batteries in one longer session: the MASS brochure describes a combined MASS/POSS battery taking about three hours. We have not seen a published combined TECH sitting.

Results usually stay with the battery, not the employer, and some utilities accept a result from another company under EEI's release process. That, and how long you must wait before a retake, are set by each employer — LG&E and KU, for example, says an applicant not selected because of their test results cannot retake the same test within 90 days.

Frequently asked questions

Is TECH harder than CAST?

Different rather than harder. TECH is aimed at technician roles that usually need an associate degree and leans on diagrams, illustrations and formal rules; CAST leans on reading and fast arithmetic. Which feels harder depends on your background.

Does Mechanical Concepts practice count for all three?

Yes. EEI's CAST, MASS and TECH brochures all describe the same 44-question, 20-minute Mechanical Concepts test, so practice carries across.

Which battery is used for drafting or GIS jobs?

TECH, according to EEI's catalog (drafter) and LG&E and KU's testing page (drafting, engineering design and GIS). Your posting is the final word.