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Here are some tips and sample technical interview questions relating to Small Plant Surveyor jobs in the integrity industry. The Matthews Integrity Hub:HEAD OFFICE website contains a series of these, relevant to different jobs in the industry. Before you read the individual sets, first have a read through our short introductory articles Technical interviews in the world of asset integrity  and Integrity job technical interviews; some facts to help put them in context.

What jobs are we talking about?

It’s those with the title ‘Engineer Surveyor’ or one of the similar titles below

  • Insurance inspector
  • Inspection surveyor
  • Pressure vessel and/or lifting equipment inspector
  • ‘Third party’ inspector

Most of these are home-based inspection roles for low technology items of pressure equipment, lifting equipment, and a few other machinery types.  The periodic in-service inspection of these items is driven by the requirements of statutory legislation (PSSR and LOLER in the UK) and government regulations, or just accepted industry practice elsewhere. Inspections are limited to fairly simple functional, visual or ultrasonic thickness check examinations with short proforma report sheets.

Some ‘small plant surveyors’ do move on to larger plant such as boilers and larger site vessels. This is normally well controlled by employers who have a

‘competency matrix’ to record their decisions as to which of their surveyors they deem competent to take this step.

Small plant surveyor interview questions; what to expect

Interview questions for these roles are generally much more routine than you may find elsewhere. Once you’ve got a basic knowledge of the equipment you will be expecting, the job is as much about your reliability, the way in which you deal with multiple clients and following your employer’s reporting procedures than anything else. Knowledge of the relevant regulations is also important, but you can learn these fairly easily on the job. Let’s look at some good small plant surveyor technical interview questions;

Question 1. The plant surveyor’s role. What is it?

Question. What is the actual purpose of the surveyor’s role in doing periodic surveys of pressure plant, lifting equipment, LEV installations and suchlike?

This question contains a few potential pitfalls. Here are some typical answers (and comments on them)

To keep people safe? (True enough I suppose)

To lower the risk for the insurers? (Indirectly it might do, but the insurance underwriters don’t commission the inspections)

To meet statutory regulations? (Yes, generally true)

To act as an enforcement authority? (No that’s the HSE’s job)

To help the Health and Safety Executive (HSE) enforce their rules? (No, they have their own inspectors for that)

To check the plant owner is following their own procedures? (Not really, that’s more a QA-audit role)

To provide a condition report, like an MOT test on a car? (Yes, a bit like that, but not in so much detail)

To act as technical adviser to the plant owner? (Debatable…. it’s more like monitoring than advice)

To protect the plant owner from the HSE (Actually yes, although it’s rarely described like that)

To act as the Competent Person (CP) defined in the PSSR or LOLER Regulations (Tempting, but the status of CP is more often the surveyor’s employer than the surveyor themselves)

As a job applicant, be warned that individual people within engineer surveyor companies can have very different views on the above list of responsibilities. Some may not have actually thought about it in that level of depth and are happy to just follow the company procedures and guidance notes. As a job candidate, be careful also how you answer this type of question. Even better, put the question to your interviewer first, so you can find out what they think.

Question 2. Pressure relief valves (PRVs)

Question. As Engineer Surveyors we are frequently required to do checks and inspections on PRVs. What should the lift ‘set’ pressure of the PRV be on an air receiver with a working pressure of 10 barG?

There are various technical views on this, making it a good area for discussion. Here are some of these views;

  • The PRV should be set to 10% above the working pressure (11 barG )
  • The PRV should be set to the MAWP (for ASME vessels) or the Design Pressure for codes (like PD5500) that do not use the principle of a calculated MAWP. This would most likely exceed 10 barG.
  • In the UK, the PSSR regulations require the designation of a SOL (Safe operating limit) which should not be exceeded in use. PRVs are designed with a ‘pressure accumulation’ characteristic, meaning that the pressure can continue to rise in the vessel until the PRV has lifted fully. This suggests the PRV should be set to say 10% below the SOL.

As a job candidate, it is good interview preparation to do some research on these options and develop your technical views on them. Engineer surveyors have frequent involvement with pressure relief valve checks and testing.

Question 3. Inspection of lifting accessories

Question. What kind of degradation or problems should an Engineer Surveyor look for on lifting equipment and accessories?

This is a straightforward technical question and relies on the candidate knowing what the various types of lifting equipment and their accessories actually are. Some typical answers are:

Lifting hoists

  • Fatigue cracking of welds
  • Permanent deflection of structure
  • Incorrect SWL marking

Cleaning cradles/suspension equipment

  • Disconnection of overload trips
  • Safety gate/catch integrity

Vehicle lifts

  • Mal-operation of brake pawls and dogs
  • Loose hydraulic piston supports
  • Bypassed trips and safety features
  • Levelness of platform

Goods and passenger lifts

  • Brake integrity; ropes, sheaves etc
  • Alignment of cab between floors
  • Door interlocks/safety features/trips
  • Alarms

Fork lift trucks

  • Fatigue of fork and structure welds
  • Chains/lift mechanism
  • Steering
  • Alarms
  • Safety features and interlocks
  • Unrecorded repairs

Wire strops and steel ropes

  • Broken strands
  • Unwinding
  • Corrosion
  • Broken crimps
  • Permanent set/distortion


  • Deformed links
  • Incorrect repairs
  • Incorrect length (in multi-chain sets)

Crane hooks

  • Opening up of hook jaw
  • Fatigue cracks


  • Breaking or stretching of threads
  • Fatigue cracking of sharp radii

Spreader bar and lifting beams

  • SWL marking
  • Fatigue cracking of lifting bracket welds
  • Permanent set/distortion
  • Broken end-fixings

When discussing subjects such as these remember that there is good technical coverage in the LOLER regulations and in the various leaflets and publications from The Health and Safety Executive (HSE).

Question 4. Written schemes of examination

Question: What would you do if you attend a periodic pressure system inspection and the plant owner has no Written Scheme of Examination (WSE) in place?

This is as much a question on the existence and content of WSEs as it is a ‘what should you do?’ type of question. Some salient points about WSEs that could form answer discussions are;

  • The existence of a WSE is prescribed by PSSR Regulation 8 and also a requirement of LOLER Regulations. In theory, if there is no WSE, then a statutory inspection cannot take place until one has been agreed. Some companies have ‘generic’ WSEs to use in such circumstances.
  • Strictly, the WSE is owned by the plant owner. Although the inspection company (Competent Person) often helps them write it. Both parties need to agree its content.
  • WSEs should include details of preparation of the equipment for testing (disassembly, removing insulation, paint etc) as well as the types of inspections required

From the employer’s point of view, the use of a comprehensive WSE is a good way to achieve a consistent level of inspection, from surveyors with differing levels of experience. Both the administrative aspects (regular WSE review etc) as well as the practical content of it are important.


If you want to check your knowledge for a specific job role in the integrity industry then try our trial technical interview.  Its purpose is to test you on the technical aspects of the job you are thinking of applying for.  There's no time limit on it but expect it to last at least 20 minutes.  After the discussion we'll give you honest feedback on how you did.  Just let us know the type of position you are going for; we'll do the rest and respond with at time slot for you to call us.

There's no charge, but we will expect you to call us at the allocated time and be ready to answer technical questions.

Remember your trial interview is on a purely technical subjects.  We are not interested in you personality traits, do-gooding activities or any wonderful extra-curricular interests you may have.

Technical Interview


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