Free DHA Central Sterile Services Technician mock test
12 original exam-style questions from our Central Sterile Services Technician bank, timed at the exam’s own pace, scored against the 50% DHA pass mark. They span 7 of the 8 blueprint domains, so you will see exactly where you are weakest - free, no sign-up.
Sit 12 original exam-style questions at real exam pace
These are 12 original questions taken from our Central Sterile Services Technician bank, spread across 7 of the 8 domains of the published blueprint. You get 72 seconds per question, which is exactly the pace of the real STE5652 exam (14 minutes for 12). At the end you will see which domains you are weakest in, and the full worked reasoning for every question.
- 12
- questions
- 14:24
- time limit
- 50%
- DHA pass mark
A short diagnostic cannot predict whether you will pass - only the real exam does that. It will show you, honestly, where you currently stand.
What the real Central Sterile Services Technician licensing exam looks like
Candidates for a Central Sterile Services Technician licence in the UAE sit a computer-based multiple-choice examination - DHA exam code STE5652, delivered through Prometric for DHA, MOHAP and SHA, and through Pearson VUE for DOH Abu Dhabi. The DHA pass mark is 50% (DHA CBT Guideline, Sep 2026); other authorities set their own, so confirm yours before booking. The result is reported to you as pass or fail only - your score is never released.
Pass marks at a glance: DHA exam codes and pass marks for all written exams in one sourced table.
The paper is built to a published blueprint, which is why a domain-by-domain diagnostic is more useful than a raw percentage. Your questions above were drawn from across Decontamination: Cleaning and Disinfection, Microbiology and Infection Prevention Principles, Monitoring, Quality Assurance and Traceability, Steam Sterilisation and 3 more - the same areas the real paper weights.
Before you can book the exam at all you need Dataflow primary source verification of your degree, licence and experience, which typically runs several weeks. Candidates routinely underestimate this and end up sitting the exam sooner after study than they planned. Check where you stand with our free eligibility checker or confirm whether your title even requires an exam using the Prometric exam checker.
You get three attempts in total across all UAE authorities - not three each - under the Unified Professional Qualification Requirements. At roughly AED 880 per attempt, plus the licensing delay each failure adds to your visa and start date, the cost of going in underprepared is not really the exam fee.
What is on the Central Sterile Services Technician exam: the full blueprint
The published blueprint splits into 8 domains and 53 testable sub-topics. The diagnostic above samples across them, which is why its breakdown maps onto the structure the real paper is built from.
- Microbiology and Infection Prevention Principles~10%6 topics
- Decontamination: Cleaning and Disinfection~18%8 topics
- Inspection, Assembly and Packaging~15%7 topics
- Steam Sterilisation~18%8 topics
- Low-Temperature Sterilisation~10%6 topics
- Monitoring, Quality Assurance and Traceability~14%7 topics
- Sterile Storage and Distribution~7%5 topics
- Workplace Safety and Professional Conduct~8%6 topics
- Questions
- 150 multiple-choice (DHA STE5652)
- Duration
- 3 hours, including registration
- DHA pass mark
- 50% - reported as pass or fail only
Figures for the DHA exam, from the DHA CBT Guideline, Sep 2026. DOH, MOHAP, SCFHS, QCHP, NHRA and OMSB set their own length, timing and pass mark. See the DHA exam guide and pass marks for every DHA exam.
A worked Central Sterile Services Technician exam question
Every question in the diagnostic and in the paid bank is written to this standard: a clinical stem, four plausible options and the reasoning for the answer, with its source.
Decontamination: Cleaning and Disinfection
Why must instruments be thoroughly cleaned before sterilisation?
- ASterilisers remove any remaining soil
- BSoil shields microbes from sterilantCorrect
- CCleaning alone makes items sterile
- DClean items need shorter cycle times
Why: Residual organic and inorganic soil protects microorganisms from steam or chemical sterilants, so items that are not clean cannot be sterilised. Cleaning is the essential first step, not a substitute for sterilisation.
Source: CDC Guideline for Disinfection and Sterilization in Healthcare Facilities 2008
Central Sterile Services Technician sample questions with answers
4 more original exam-style Central Sterile Services Technician questions, worked in full. They are not real or recalled exam questions, and none of them is in the diagnostic above, so sit that first if you have not.
Question 1 · Decontamination: Cleaning and Disinfection
Why is treated water such as reverse osmosis water preferred for the final rinse of instruments?
- AIt is cheaper than tap water
- BIt sterilises instruments on contact
- CIt limits spotting and endotoxin residue
- DIt removes the need for drying
Show answer and explanation
Correct answer: C. It limits spotting and endotoxin residue
Treated water with low minerals and endotoxin prevents staining, corrosion and residues that can harm patients. It does not sterilise instruments, and drying is still needed.
Reference: AAMI ST108: Water for the Processing of Medical Devices
Question 2 · Inspection, Assembly and Packaging
To reduce wet packs and handling injury, what is the maximum recommended weight of a wrapped instrument tray including its container or wrap?
- A5 kg (11 lb)
- B11.3 kg (25 lb)
- C16 kg (35 lb)
- D20 kg (44 lb)
Show answer and explanation
Correct answer: B. 11.3 kg (25 lb)
AAMI recommends that instrument sets weigh no more than 25 lb (about 11.3 kg) in total. Heavier sets cause condensation and wet packs and are an ergonomic risk.
Reference: AAMI ST79: Comprehensive Guide to Steam Sterilization in Health Care Facilities
Question 3 · Inspection, Assembly and Packaging
Insulated laparoscopic diathermy instruments are being assembled. What check is needed in addition to visual inspection?
- ASoaking them in saline to find leaks
- BInsulation testing with a tester
- CLubricating the insulated shaft
- DTapping the shaft to hear cracks
Show answer and explanation
Correct answer: B. Insulation testing with a tester
Insulation breaches may be invisible, so insulated instruments are checked with an insulation tester, as damaged insulation can cause stray-current burns. Visual inspection alone misses small defects.
Reference: AAMI ST79: Comprehensive Guide to Steam Sterilization in Health Care Facilities
Question 4 · Low-Temperature Sterilisation
Why must items sterilised with ethylene oxide be aerated before use?
- ATo activate the chemical indicator
- BTo cool them after a high-temperature cycle
- CTo dry condensed steam
- DTo remove toxic EO residues
Show answer and explanation
Correct answer: D. To remove toxic EO residues
Ethylene oxide is toxic and carcinogenic and is absorbed into materials, so aeration is required to reduce residues to safe levels. EO cycles are low-temperature and do not use steam.
Reference: ISO 10993-7: Ethylene Oxide Sterilization Residuals
How to use this diagnostic properly
- 1Sit it cold, once. Do not look anything up. A diagnostic you help yourself through tells you nothing. The number you get is only useful if it is honest.
- 2Read every rationale - especially the ones you got right. Getting a question right by elimination is not the same as knowing it. The worked reasoning is free above, whether or not you buy anything.
- 3Work weakest domain first. The breakdown orders your domains worst-first for exactly this reason. Studying what you are already good at feels productive and moves nothing.
- 4Re-sit under full exam conditions later. The real paper is far longer than this and stamina matters. Full-length timed papers are what the paid bank is for.