100 Questions to Ask: How Khash Understands Whether a Lubrication Specialist Has Practical Experience

A lubrication specialist can sound very knowledgeable in an interview. Many candidates can define viscosity, additives, ISO cleanliness, grease consistency, or oil analysis. The real challenge is different: has the person actually worked with machines, lubricants, samples, contamination, grease guns, failed bearings, storage rooms, routes, technicians, reports, and shutdown pressure?

That is why Khash’s approach is not to ask only textbook questions. His method is to ask practical, evidence-based questions that force the candidate to explain what they did, what they saw, what decision they made, what result followed, and what they would change next time.

This approach aligns with how the lubrication profession is normally defined. STLE’s Certified Lubrication Specialist role includes lubricant selection, lube surveys, training lubricators, developing used-oil analysis programs, troubleshooting lubrication problems, and maintaining application and waste records. (stle.org) ICML’s machinery lubrication and oil-analysis certifications also emphasize lubrication theory, lubricant application, storage, sampling, contamination control, condition monitoring, and program management, rather than theory alone. (icmlonline.com) ISO 18436-4 specifically addresses qualification and assessment of people who perform field lubricant analysis for machinery condition monitoring. (ISO)

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1. The Core Idea Behind Khash’s Interview Method

Khash does not ask, “Do you know lubrication?”

He asks questions that reveal whether the candidate can:

1. Diagnose a lubrication-related problem.
2. Select the correct lubricant or grease based on machine conditions.
3. Apply the lubricant correctly in the field.
4. Control contamination from storage to machine.
5. Take representative oil samples consistently.
6. Interpret oil analysis results practically.
7. Connect oil data to machine condition.
8. Build a lubrication program, not just talk about one.
9. Train others and improve behavior.
10. Defend decisions with evidence, not guesses.

The difference between a practical candidate and a theoretical candidate appears quickly. A theoretical candidate gives definitions. A practical candidate explains actual decisions: “I moved the sample point upstream of the filter,” “I changed the breather type because water was entering the reservoir,” “I reduced grease quantity after calculating bearing free space,” or “I rejected new oil because the incoming cleanliness code was outside target.”

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2. The Interview Framework

Step 1: Ask the question in a real plant context

Avoid questions like:

“What is viscosity?”

Ask instead:

“You have a hot-running gearbox. The oil viscosity is lower than expected, oxidation is rising, and the operator says the gearbox was topped up twice last month. What do you check first?”

This reveals whether the candidate understands lubricant degradation, wrong top-up oil, leakage, overheating, contamination, and sampling consistency.

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Step 2: Ask for evidence

Khash should follow each answer with:

“Where have you done this before?”
“What machine was it?”
“What was the oil grade?”
“What did the report show?”
“What action did you take?”
“What was the result?”

A practical lubrication specialist usually remembers machine types, symptoms, corrective actions, and lessons learned. A weak candidate usually stays general.

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Step 3: Use a 0–4 scoring system

Score	Meaning	Answer Type
0	No understanding	Incorrect or unsafe answer
1	Memorized theory	Can define terms but cannot apply them
2	Basic practical awareness	Understands the issue but lacks depth or field evidence
3	Good field experience	Gives correct steps, examples, and reasonable judgment
4	Strong practical specialist	Gives diagnosis, evidence, priorities, risks, standards, and measurable results

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Step 4: Apply an evidence multiplier

After scoring the technical answer, Khash can apply an evidence factor:

Evidence Level	Multiplier	Meaning
No real example	×0.75	Candidate is probably theoretical
One general example	×1.00	Acceptable but needs probing
Specific machine example	×1.15	Shows real exposure
Specific example with data and result	×1.30	Strong practical evidence

Example:

A candidate gives a good answer on oil sampling and scores 3 out of 4. Then he explains that he installed a dedicated sampling valve on a hydraulic return line, flushed the sample port, standardized bottle labeling, and improved trend consistency. Khash can multiply the score by 1.30, because the candidate gave specific practical evidence.

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3. Recommended Weighting of the 10 Sections

Section	Weight
1. Lubrication Theory/Fundamentals	8%
2. Lubricant Selection	10%
3. Lubricant Application	10%
4. Lube Storage and Management	10%
5. Lube Condition Control	10%
6. Oil Sampling	12%
7. Lubricant Health Monitoring	10%
8. Wear Debris Monitoring and Analysis	10%
9. Oil Analysis Program Development and Management	12%
10. Grease Application and Performance	8%
Total	100%

Oil sampling and program management receive high weight because weak sampling and weak program ownership can destroy the value of even the best laboratory testing. ASTM D4057 and ASTM D4177 both emphasize the importance of representative petroleum-product sampling, although their exact applications differ. (ASTM International | ASTM)

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4. The 100 Questions

Each section contains 10 questions. The purpose is not only to check knowledge. The purpose is to expose whether the candidate has actually performed lubrication work.

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Section 1: Lubrication Theory/Fundamentals

No.	Question	Practical answer should include	Weak answer usually sounds like
1	Explain the difference between hydrodynamic, elastohydrodynamic, mixed, and boundary lubrication using real machine examples.	Journal bearings, rolling bearings, gears, start-stop conditions, load/speed/viscosity relationship.	Only textbook definitions.
2	A bearing fails repeatedly after startup, but not during steady operation. What lubrication regime might be involved?	Boundary or mixed lubrication during startup, wrong viscosity, poor grease/oil film, contamination, insufficient pre-lube.	“Use better oil.”
3	How does viscosity affect film thickness, heat generation, and energy consumption?	Higher viscosity may improve film but increase drag and heat; lower viscosity may reduce film and increase wear.	“Thicker oil is always better.”
4	What happens when oil operates above its recommended temperature range?	Oxidation, viscosity change, additive depletion, varnish, shorter oil life.	“Oil becomes thin.”
5	How do speed, load, and temperature influence lubricant selection?	High speed may need lower viscosity; high load may need EP/AW; high temperature may need oxidation stability.	Generic “follow OEM.”
6	What is the role of additives in lubricants?	AW, EP, antioxidants, rust inhibitors, demulsifiers, detergents, dispersants, VI improvers depending on oil type.	“Additives make oil stronger.”
7	How do you recognize lubricant starvation in the field?	Noise, heat, discoloration, wear, vibration, dry components, low level, blocked lines, poor distribution.	“Machine will stop.”
8	Why can over-lubrication be as harmful as under-lubrication?	Heat, churning, seal damage, grease purge, energy loss, contamination attraction.	“More lubricant is safer.”
9	What is the difference between friction, wear, and lubrication failure?	Friction is resistance, wear is material loss, lubrication failure is loss of separating film or lubricant function.	Confuses all three.
10	Give an example where changing lubrication practice improved machine reliability.	Specific machine, issue, change, result.	No example.

Gap analysis for Section 1:
The practical candidate connects theory to actual machines. The weak candidate uses definitions but cannot explain what happens during startup, overheating, over-greasing, contamination, or wrong viscosity.

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Section 2: Lubricant Selection

No.	Question	Practical answer should include	Weak answer usually sounds like
11	How do you select oil viscosity for a gearbox?	OEM recommendation, speed, load, operating temperature, gear type, sump temperature, viscosity index.	“Use ISO VG 220 because gearboxes use 220.”
12	When would you consider synthetic oil?	High/low temperature, extended drain, oxidation control, energy efficiency, compatibility check, cost justification.	“Synthetic is always better.”
13	How do you verify if two lubricants are compatible?	Supplier data, compatibility testing, base oil/additive chemistry, seal compatibility, flushing plan.	“Same viscosity means compatible.”
14	What factors affect hydraulic oil selection?	Viscosity, pump type, pressure, temperature, anti-wear chemistry, demulsibility, air release, cleanliness target.	“Use hydraulic oil 68.”
15	How do you select compressor oil?	Compressor type, gas compatibility, discharge temperature, oxidation, varnish tendency, OEM requirement.	“Use compressor oil.”
16	What is the risk of using EP gear oil in the wrong application?	Yellow metal compatibility, additive interaction, seal compatibility, foaming, OEM restrictions.	“EP is stronger, so it is better.”
17	How do you consolidate lubricants in a plant without creating risk?	Survey assets, map OEM specs, identify duplicates, check compatibility, approve equivalent products, update labels/routes.	“Reduce brands.”
18	What information do you need before approving a lubricant substitution?	OEM spec, viscosity, performance standards, base oil, additives, compatibility, operating conditions, warranty impact.	“Ask supplier.”
19	What does the viscosity index tell you practically?	How viscosity changes with temperature; useful for wide temperature ranges.	“It is the viscosity.”
20	Describe a wrong-lubricant incident and how you would investigate it.	Check top-up records, storage labels, oil analysis, viscosity, additive elements, operator practice, corrective action.	“Drain and refill.”

Gap analysis for Section 2:
The practical candidate treats lubricant selection as an engineering decision. The weak candidate chooses by habit, brand name, or viscosity alone.

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Section 3: Lubricant Application

No.	Question	Practical answer should include	Weak answer usually sounds like
21	How do you decide oil-change frequency?	OEM starting point, oil analysis trends, environment, duty, contamination, oxidation, criticality.	“Every six months.”
22	How do you prevent cross-contamination during top-up?	Dedicated containers, labeling, color coding, sealed transfer, training, audits.	“Be careful.”
23	What checks do you perform before topping up a gearbox?	Correct oil, level, leaks, breather, contamination, temperature, reason for low level.	“Add oil until full.”
24	How do you know if an automatic lubricator is working correctly?	Grease movement, line blockage, setting, consumption, back pressure, bearing response, inspection.	“It is installed, so it works.”
25	How do you flush a system after wrong oil was added?	Risk assessment, drain, circulate flushing oil if needed, filter, inspect, sample, confirm cleanliness/compatibility.	“Drain it once.”
26	What information should be included in a lubrication procedure?	What, where, lubricant, quantity, frequency, method, safety, tools, acceptance criteria, record.	“Apply grease monthly.”
27	How do you avoid overfilling a bearing housing or gearbox?	Level marks, sight glass, correct machine state, expansion allowance, inspection procedure.	“Fill to the top.”
28	How do you train operators to notice lubrication problems?	Visual checks, abnormal sound, temperature, leaks, color, smell, foaming, low level, reporting path.	“Tell them to check oil.”
29	What is your method for auditing a lube route?	Walkdown, task verification, tools, labels, quantities, missed points, CMMS records, technician feedback.	“Check the route sheet.”
30	What would you do if maintenance says, “We have always greased it this way”?	Review failure history, calculate quantity/frequency, observe practice, trial improvement, show evidence.	“Accept it.”

Gap analysis for Section 3:
Practical experience appears in the candidate’s ability to explain exact field steps. Weak candidates answer in general instructions without quantities, routes, tools, or verification.

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Section 4: Lube Storage and Management

No.	Question	Practical answer should include	Weak answer usually sounds like
31	What does a good lube room look like?	Clean, dry, labeled, sealed, ventilated, controlled inventory, spill control, dedicated transfer tools.	“Oils stored in one place.”
32	How do you prevent contamination in stored oil?	Desiccant breathers, sealed containers, filtration, clean dispensing, drum handling, moisture control.	“Keep drums closed.”
33	What are the risks of storing drums outside?	Water ingress, temperature cycling, rust, damaged labels, dirt, wrong handling.	“No problem if sealed.”
34	How do you manage lubricant shelf life?	FIFO, supplier guidance, date received/opened, condition inspection, testing if aged.	“Oil does not expire.”
35	How should lubricants be labeled?	Product name, viscosity, application, color/shape code, date, safety info, matching machine tags.	“Write oil name.”
36	How do you receive new oil at site?	Check delivery, COA, packaging, cleanliness if required, correct product, batch, sample if critical.	“Put it in the store.”
37	Why might new oil need filtration before use?	New oil can be cleaner or dirtier than machine target; critical systems may require pre-filtration.	“New oil is always clean.”
38	How do you avoid mixing greases in storage and application?	Dedicated guns, labels, compatibility chart, training, controlled issue.	“Use any grease gun.”
39	What records should be kept for lubricant inventory?	Stock, batch, receipt date, issue quantity, machine usage, reorder point, disposal.	“Purchase records only.”
40	How do you reduce lubricant consumption?	Leak control, correct application, route optimization, contamination control, oil analysis-based drains.	“Buy less oil.”

Gap analysis for Section 4:
The practical candidate sees storage as the first step in machine reliability. The weak candidate sees storage as housekeeping only.

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Section 5: Lube Condition Control

No.	Question	Practical answer should include	Weak answer usually sounds like
41	What contaminants are most damaging to lubricated equipment?	Particles, water, air, heat, wrong lubricant, process contamination.	“Dirt.”
42	How do you set an oil cleanliness target?	OEM guidance, component sensitivity, pressure, criticality, ISO code, reliability goals.	“Cleaner is better.”
43	What does ISO 4406 measure?	Solid particle contamination coding for hydraulic fluids; used widely for cleanliness control.	“Oil quality number.”
44	How do you control water contamination?	Breathers, seals, storage control, dehydration, centrifuge/vacuum dehydration, root-cause repair.	“Drain the water.”
45	What is the difference between dissolved, emulsified, and free water?	Different water states; different detection/removal methods and risks.	“Water is water.”
46	How do you detect air entrainment or foaming problems?	Visual inspection, oil analysis, foam tendency, low level, suction leaks, wrong oil, return-line design.	“Add anti-foam.”
47	When would you use offline filtration?	Critical systems, high ingression, poor built-in filtration, cleanup after maintenance, target cleanliness.	“When oil looks dirty.”
48	What is varnish, and where is it a concern?	Oxidation/degradation deposits; turbines, compressors, hydraulics, servo valves.	“Dark oil.”
49	How do temperature and contamination interact?	Heat accelerates oxidation; contamination accelerates wear and degradation.	“Both are bad.”
50	What is your contamination-control improvement plan for a dirty hydraulic system?	Baseline sample, target ISO code, root-cause ingress control, filtration, breathers, seals, monitoring.	“Change oil.”

ISO 4406:2021 specifies a method for coding the level of solid-particle contamination in hydraulic fluid power systems. (ISO) Practical candidates should understand cleanliness codes as decision tools, not just numbers on a report.

Gap analysis for Section 5:
Practical candidates move from “detect contamination” to “remove it and stop it from coming back.” Weak candidates only suggest changing oil.

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Section 6: Oil Sampling

No.	Question	Practical answer should include	Weak answer usually sounds like
51	What makes an oil sample representative?	Correct point, running condition, repeatable method, clean bottle, flushing, labeling, timing.	“Any oil from the machine.”
52	Where would you sample a circulating system?	Live zone, turbulent line, before filter for wear, after filter for filter performance if needed.	“From the drain.”
53	Why is sampling from a drain plug often misleading?	Sediment/water collection, non-representative dead zone, inconsistent results.	“It is easiest.”
54	What information must be written on a sample bottle/form?	Asset ID, oil type, hours, date, sample point, top-up, oil change, abnormal conditions.	“Machine name.”
55	Why should sampling method be consistent?	Trend accuracy; changing point/method changes data.	“Lab will know.”
56	How do you flush a sample valve before taking the sample?	Remove stagnant oil/debris, use correct volume, avoid contamination, then fill bottle properly.	“Open and fill.”
57	How soon should samples be sent to the lab?	As soon as practical; avoid delays that reduce decision value.	“Whenever courier comes.”
58	What is the difference between routine, exception, and confirmation samples?	Scheduled trend, abnormal investigation, post-correction verification.	“All samples are same.”
59	How do you choose sample frequency?	Criticality, failure history, oil volume, environment, duty cycle, cost of failure.	“Monthly for all machines.”
60	Describe a time when a bad sample caused a wrong decision.	Candidate explains sampling error, false alarm/missed alarm, correction.	No experience.

ASTM D4057 highlights that sampling has inherent limitations and that the representative nature of a sample can be affected by sampling choices. (ASTM International | ASTM) That is why Khash gives oil sampling a high score weight.

Gap analysis for Section 6:
A practical candidate knows that oil analysis begins before the lab. A weak candidate thinks the laboratory alone determines the quality of the result.

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Section 7: Lubricant Health Monitoring

No.	Question	Practical answer should include	Weak answer usually sounds like
61	Which tests show lubricant degradation?	Viscosity, oxidation, TAN/TBN where relevant, FTIR, RPVOT for turbines, MPC for varnish tendency.	“Oil analysis test.”
62	What does a viscosity increase indicate?	Oxidation, contamination, wrong oil, soot in engines, evaporation, thermal stress.	“Oil got thicker.”
63	What does a viscosity decrease indicate?	Fuel dilution, wrong top-up, shearing, solvent contamination, thermal cracking.	“Oil got thinner.”
64	How do you interpret TAN increase?	Acid formation, oxidation, additive depletion, compare baseline and trend.	“Oil is bad.”
65	How do you know when to change oil based on condition?	Trend limits, alarms, lubricant health, contamination, wear, machine criticality.	“When color changes.”
66	What is the value of a new-oil baseline?	Compare used oil to original properties and additive elements.	“Lab already knows.”
67	How do you detect wrong oil through analysis?	Viscosity mismatch, additive fingerprint, elemental differences, FTIR, records.	“Color is different.”
68	What is additive depletion?	Loss/consumption of protective chemistry; depends on additive type and application.	“Additives disappear.”
69	How do you handle conflicting oil analysis results?	Check sample quality, resample, compare trend, verify lab method, inspect machine.	“Ignore one result.”
70	Give an example where oil health monitoring prevented failure.	Specific abnormal trend, action, result.	No example.

Gap analysis for Section 7:
The practical specialist interprets trends, not single numbers. The weak candidate reacts to one abnormal value without checking context.

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Section 8: Wear Debris Monitoring and Analysis

No.	Question	Practical answer should include	Weak answer usually sounds like
71	What wear metals are commonly associated with bearings, gears, and bushings?	Iron, copper, lead, tin, chromium, aluminum depending on component metallurgy.	“Metal particles.”
72	What is the difference between normal wear and abnormal wear?	Trend rate, particle size, morphology, operating condition, baseline comparison.	“High metal is bad.”
73	How do you distinguish cutting wear from fatigue wear?	Particle shape, size, ferrous density, analytical ferrography, machine context.	“Lab will say.”
74	What does high silicon with high wear metals suggest?	Dirt ingress causing abrasive wear, depending on oil/additive chemistry.	“Silicon means sealant only.”
75	What does high iron after overhaul mean?	Break-in wear, poor cleaning, contamination, alignment issue, wrong lubricant; trend is important.	“Machine is failing.”
76	What is ferrous density useful for?	Detecting magnetic wear debris, severity trend, large particles missed by spectroscopy.	“Iron test.”
77	Why can spectroscopy miss large wear particles?	Large particles may not be fully detected depending on method limitations.	“All metals are measured.”
78	How do you use filter debris inspection?	Cut/open inspect filters, analyze debris, identify abnormal wear, plan corrective action.	“Replace filter only.”
79	When would you escalate from routine oil analysis to wear debris analysis?	Rising wear, abnormal vibration, critical asset, filter debris, unexplained alarms.	“When lab says.”
80	Describe a case where wear debris changed your maintenance decision.	Candidate links particles to inspection or shutdown decision.	No example.

ASTM D7898 covers extraction, analysis, and information management for visible wear debris collected from oil filters or debris retention screens for machinery condition monitoring. (ASTM International | ASTM)

Gap analysis for Section 8:
A practical candidate uses wear debris to understand failure mode and urgency. A weak candidate only reads elemental numbers from the lab report.

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Section 9: Oil Analysis Program Development and Program Management

No.	Question	Practical answer should include	Weak answer usually sounds like
81	How do you start an oil analysis program from zero?	Asset criticality, machine list, sampling points, test slate, frequency, limits, lab selection, workflow.	“Send samples to lab.”
82	How do you decide which machines enter the program?	Criticality, failure cost, oil volume, failure history, safety, production impact.	“All machines.”
83	How do you choose the correct test package?	Machine type, lubricant type, failure modes, contamination risks, lubricant health, wear monitoring.	“Standard package.”
84	How do you set alarm limits?	OEM, lab guidance, baseline, statistical trends, criticality, lubricant/machine-specific limits.	“Use lab default.”
85	What KPIs would you track?	Sample compliance, abnormal closure time, contamination levels, oil changes avoided, failures prevented, route compliance.	“Number of samples.”
86	How do you make sure reports lead to action?	Responsibility matrix, severity coding, CMMS work orders, follow-up samples, closure tracking.	“Email the report.”
87	How do you handle overdue samples?	Dashboard, planner involvement, route ownership, escalation, reason analysis.	“Remind technician.”
88	How do you prove program value to management?	Avoided failures, extended drains, reduced oil consumption, reduced downtime, contamination improvement.	“Oil analysis is good.”
89	How do you train technicians in sampling and lubrication routes?	Procedure, demonstration, competency check, audits, feedback, refresher training.	“Give presentation.”
90	What are common reasons oil analysis programs fail?	Poor sampling, no ownership, wrong tests, ignored reports, no corrective action, weak data quality.	“Bad lab.”

ICML’s Machinery Lubrication Engineer body of knowledge explicitly emphasizes practical knowledge for lubrication and reliability engineers working with lubricated physical assets, not purely academic knowledge. (icmlonline.com)

Gap analysis for Section 9:
A practical candidate understands that oil analysis is a management system. A weak candidate treats it as a laboratory activity only.

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Section 10: Grease Application and Performance

No.	Question	Practical answer should include	Weak answer usually sounds like
91	How do you calculate grease quantity for a bearing?	Bearing dimensions, formula or OEM guidance, speed, housing type, purge path, interval.	“Two or three pumps.”
92	Why should grease guns be calibrated?	Pump output varies; correct quantity requires grams per stroke.	“All grease guns are same.”
93	What happens when a motor bearing is over-greased?	Heat, churning, seal damage, grease entering windings, failure risk.	“Extra grease comes out.”
94	How do you choose grease NLGI grade?	Application, temperature, speed, load, pumping system, bearing type.	“NLGI 2 for everything.”
95	What is grease compatibility?	Thickener/base oil/additive compatibility; mixing can cause softening, hardening, oil bleed.	“Same color means compatible.”
96	When would you use EP grease?	High load/shock load, slow speed, suitable metallurgy/application, OEM approval.	“EP is always better.”
97	How do you troubleshoot grease leaking from seals?	Over-greasing, wrong consistency, blocked purge, heat, seal damage, wrong grease.	“Seal is bad.”
98	How do you lubricate slow-speed heavily loaded bearings?	Correct viscosity/base oil, EP/solid additives if needed, quantity, relube interval, contamination control.	“Use thick grease.”
99	How do automatic greasing systems fail?	Blocked lines, wrong setting, empty reservoir, wrong grease, injector failure, no verification.	“They do not fail.”
100	Describe a real case where grease practice caused or solved a failure.	Specific bearing/motor, quantity/frequency, analysis, correction, result.	No field example.

Gap analysis for Section 10:
The practical candidate knows grease is not “simple lubrication.” Quantity, frequency, compatibility, delivery method, and verification matter. The weak candidate believes greasing is only applying more grease.

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5. How Khash Grades the Candidate

Khash can use a scoring sheet like this:

Section	Max Score	Candidate Score	Evidence Multiplier	Final Score
Lubrication Theory/Fundamentals	8
Lubricant Selection	10
Lubricant Application	10
Lube Storage and Management	10
Lube Condition Control	10
Oil Sampling	12
Lubricant Health Monitoring	10
Wear Debris Monitoring and Analysis	10
Oil Analysis Program Development	12
Grease Application and Performance	8
Total	100

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6. Interpretation of Final Score

Final Score	Interpretation
85–100	Strong practical lubrication specialist; can lead programs and mentor others.
70–84	Good candidate; practical experience exists but may need development in some areas.
55–69	Mixed profile; may be useful in technician role but not yet specialist level.
40–54	Mostly theoretical or narrow experience; needs structured training and supervision.
Below 40	Not suitable for specialist role at this stage.

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7. Gap Analysis Model

After the interview, Khash should not only say, “Candidate A scored 76.” He should identify the candidate’s practical gaps.

Example Gap Categories

Gap Type	What It Means	Example
Knowledge gap	Candidate does not understand concept	Cannot explain viscosity-temperature relationship
Application gap	Knows theory but cannot apply it	Knows ISO cleanliness but cannot set targets
Evidence gap	Gives no real examples	Claims sampling experience but cannot describe sample point
Decision gap	Cannot prioritize corrective action	Recommends oil change for every abnormal report
Program gap	Cannot manage system	No idea how to track overdue samples or corrective actions
Leadership gap	Cannot influence technicians	No method for training, auditing, or improving routes

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Practical vs. Non-Practical Answer Comparison

Interview Area	Practical Answer	Theoretical / Weak Answer	Gap
Oil sampling	“I sample from a live zone while the machine is running, flush the valve, label the bottle with hours and top-up history, and keep the method consistent.”	“Take oil and send to lab.”	Does not understand representativeness.
Greasing	“I calibrate the grease gun, calculate quantity, check purge path, and adjust interval based on bearing speed and duty.”	“Give two pumps every week.”	Habit-based lubrication.
Storage	“Each oil has dedicated sealed transfer containers, filtration, labeling, and FIFO control.”	“We keep drums in the store.”	No contamination-control mindset.
Oil analysis	“I compare result to baseline, trend, operating hours, and recent maintenance before recommending action.”	“If the lab marks red, change oil.”	No diagnostic thinking.
Lubricant selection	“I check OEM spec, viscosity at operating temperature, load, speed, temperature, compatibility, and environment.”	“Use the same oil we always use.”	No engineering selection process.
Program management	“I track sample compliance, abnormal closure time, repeat alarms, and corrective actions in CMMS.”	“The lab sends reports.”	No ownership.

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8. Practical Case Study: How Khash Used the 100 Questions to Find the Best Lubrication Talent

The following case study is written as an anonymized practical scenario that can be adapted to a real company situation.

Background

A large industrial plant invited Khash to support interviews for a lubrication specialist position. The plant had recurring problems: hydraulic failures, gearbox overheating, inconsistent oil analysis reports, excessive grease consumption, and a lube room that looked organized from the outside but had serious contamination-control weaknesses.

The hiring team had already interviewed several candidates. Most candidates had strong CVs. Some had certifications. Some had worked in maintenance for many years. But the company was not sure who had real lubrication experience and who had only general mechanical maintenance exposure.

Khash proposed using the 100 Questions to Ask method.

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Interview Design

Each candidate was interviewed in four stages:

Stage 1: Technical interview

Khash asked selected questions from all 10 sections. He did not ask all 100 questions in one sitting. Instead, he selected around 35–45 questions depending on the candidate’s claimed experience.

Stage 2: Report interpretation

Each candidate received a sample oil analysis report showing:

• Rising particle count.
• Increasing iron.
• Slight viscosity change.
• High water level.
• Repeated abnormal results from the same hydraulic system.

The candidate had to explain what could be happening and what action should be taken.

Stage 3: Field scenario

Candidates were shown photos of:

• Oil drums stored outside.
• Open funnels.
• Unlabeled grease guns.
• Breathers in poor condition.
• A gearbox sight glass showing cloudy oil.

They had to identify risks and propose corrective actions.

Stage 4: Program management discussion

Khash asked how the candidate would build a lubrication program in the first 90 days.

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Candidate Results

Candidate	Strength	Weakness	Khash’s Finding
Candidate A	Good theory and terminology	No strong field examples	More of a classroom candidate
Candidate B	Strong mechanical maintenance background	Weak oil analysis and contamination control	Good technician, not specialist yet
Candidate C	Strong oil analysis interpretation	Weak grease and storage knowledge	Useful analyst, needs plant lubrication exposure
Candidate D	Strong practical examples across sampling, storage, contamination, lubricant selection, and greasing	Needed minor improvement in formal reporting	Best fit for specialist role

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The Key Moment

The strongest candidate was not the person with the most polished CV. The strongest candidate was the one who answered with practical detail.

When asked about oil sampling, Candidate D said:

“First I check whether the current sample point is actually representative. If the sample is from a drain port, I do not trust it for trending. I prefer a live-zone sample point while the machine is running and at normal temperature. I flush the valve, use a clean bottle, record machine hours, oil hours, top-up volume, and recent maintenance. If the result is abnormal, I resample before making a costly decision.”

That answer showed practical understanding. It covered sample location, machine condition, flushing, bottle control, documentation, trending, and decision discipline.

When asked about greasing, the same candidate said:

“Before changing grease frequency, I check bearing type, speed, operating temperature, environment, purge path, and grease gun output. I do not accept ‘two pumps every week’ unless we know the pump output and required quantity.”

That answer showed that the candidate had actually seen over-greasing and understood quantity control.

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Why the Questionnaire Worked

The questionnaire helped Khash separate candidates into three groups:

1. People who know lubrication words.
2. People who have performed lubrication tasks.
3. People who can diagnose, improve, and manage lubrication reliability.

The company needed the third type.

The 100-question method revealed that Candidate D had:

• Worked with real sample points.
• Understood contamination control.
• Knew how to read oil analysis trends.
• Could challenge bad plant habits respectfully.
• Understood grease quantity and frequency.
• Could build a lubrication program, not just perform tasks.
• Could explain failures using evidence.

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9. Final Practical Recommendation from Khash

Khash’s final recommendation was not based only on interview confidence. It was based on evidence density.

The best lubrication specialist is usually the candidate who can explain:

• What machine was involved.
• What lubricant was used.
• What failure or abnormality appeared.
• What data was checked.
• What decision was made.
• What result followed.
• What lesson was learned.

That is the difference between someone who has studied lubrication and someone who has practiced lubrication.

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10. Conclusion

The title “Lubrication Specialist” should not be given to someone simply because they know lubricant terminology. A real specialist connects lubricant selection, application, contamination control, oil sampling, lubricant health, wear debris, grease practices, and program management into one reliability system.

Khash’s 100 Questions to Ask method works because it does not allow candidates to hide behind general answers. It forces them to prove experience through examples, numbers, decisions, and consequences.

A practical lubrication specialist does not only answer:

“What is the right oil?”

A practical lubrication specialist asks:

“For which machine, under what load, at what temperature, with what contamination risk, using what application method, monitored by what test, and controlled by what program?”

That is the level of thinking Khash looks for.