Staff Skills and training

Staffing and Skills Levels

Staff Training and Competence

Issues of Consistency of Evaluation of Test Results

Staffing and Skills Levels

A laboratory engaged in physical testing of textiles will require at least one graduate textile technologist who will normally be the laboratory manager. There will be no need for further graduate staff except in a laboratory with a high capacity. In this case supervisory staff should be graduate or diploma level textile technologists and there will need to be one supervisor per six staff.

Leather testing laboratories require a similar arrangement but with leather technologists rather than textile technologists.

Experience in the relevant industry at the production level is an extremely useful asset for management in a textile or leather testing laboratory. Indeed without such experience communications with customers may be difficult.

Laboratories which carry out compositional testing of textiles and basic screening for contaminants such as formaldehyde and azo dyes will not need to have a graduate chemist. Most textile and leather technologists will have had training in this kind of basic testing. It is, advisable, however to designate specific staff for the chemical work so that they develop their skills more effectively than if they only carry out this type of testing occasionally.

Textile and leather technologists will not normally have the relevant skills to carry out the more sophisticated instrumental tests such as trace metals analysis, ion chromatography for chromium (VI) and residues work such as analysis for chlorinated compounds. Laboratory’s operating in these areas will need a graduate chemist to manage the activities

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Staff Training and Competence

Especially if laboratories are seeking accreditation there will need to be a formal staff training system and full records of which staff are assessed as competent and authorised to carry out each test. In addition to tests the training and records will need to cover other technical activities, e.g. calibration or verification of equipment, and administrative procedures related to the laboratory such as sample logging, contract review and also internal auditing.

Training in Test Methods and Procedures

The following steps are required in training and assessment to met ISO 17025 typical requirements.

• Plan the training to be given and identify appropriate trainers. The trainers must be staff already authorised for the relevant activities and ideally with at least one year of experience. Below is shown a suitable format for planning and recording training in summary.

   

• The training is initiated as follows.

  • Then staff member is provided with the relevant documentation and asked to read it.

  • The documentation is then discussed with the trainer to deal with any issues arising and to make sure the trainee is clear about the procedure.

  • The procedure is demonstrated and the trainee encouraged to ask questions.

  • The trainee is then asked to carry out the procedure under supervision and advised of any problems arising.

     

• The trainee begins to carry out the procedure on a routine basis but always under close supervision from someone already authorised for the procedure. Any records or results which have to be made are checked and signed by the supervisor. The supervisor provides ongoing advice and training.

   

• When the trainer is satisfied that the trainee can be considered competent then a formal assessment of competence is organised. The assessor should, where possible, be someone other than the trainer. This may not always be possible as sometimes the area of expertise is such that only one person in the laboratory may be fully conversant with it and so able to make an assessment of competence. The assessment includes the following steps.

   

  • The trainee is asked to explain the method to the assessor and then answers questions, especially on the content of the documentation.

  • The trainee is asked to perform the procedure whilst the assessor observes. The objective is to ensure the trainee follows the correct procedure and techniques.

  • If the procedure involves testing of samples the trainee should be asked to test samples for which the result is known. These may be reference materials or simply some samples which have already been tested.

• The trainee’s performance is evaluated. The assessor should be satisfied on the following points.

   

  • The trainee understands the documentation and the procedure at an adequate level. The key issue is that the trainee knows enough to understand when the procedure does not perform as expected. Technical staff would not be expected to show a detailed knowledge of the theory behind complex test methods.

     

  • The trainee can be relied upon to perform the procedure as documented.

  • n the case of testing the trainee obtains a correct result in the sense that it meets the laboratory’s normal quality control criteria for the method and is not significantly different from the expected result bearing in mind the known uncertainty of measurement.

     

  • Copies of any results generated with an evaluation must be included in the record of the assessment to provide objective evidence of competence.

     

• The assessor prepares a report on the assessment and, if satisfied on the above points, recommends the trainee be authorised at a provisional or first level for the test. The report must be reviewed by the laboratory manager or the quality manager who gives the final authorisation. An example of a dformat for such a report is shown below.

   

• When authorised at the first level the trainee may carry out the test or procedure unsupervised but any results, findings or data must be checked and countersigned by a supervisor.

• After a period of provisional authorisation, which should be at least one month, the trainer may recommend the trainee undergo a second test of competence. This follows the same format as the initial test of competence described above and is assessed and reported in the same way.

• If the trainee passes this second test they receive full authorisation to conduct the procedure. They may sign all documents and results without any independent checks.

Review of Competence

Management must keep the competence of staff under constant review. The inputs to this process will typically include the following.

• Review the quality control data for all methods at least monthly. Take notice if any particular staff members have a higher instance of quality control issues than others.

• Ensure that any proficiency testing is carried out by as wide a range of staff as possible and identify any problem areas. Where a staff member carries out work on proficiency test samples ensure the results and an evaluation are included in their training record.

• If any staff are felt to be underperforming the issues should be discussed with them and suspension of authorisation pending further training considered.

   

There should be a formal annual review of competence of all staff coupled with a technical audit of the methods. Each staff member must undergo the following scrutiny for all tests for which they are authorised.

• They must be observed conducting the test to ensure they follow the documented procedure.

• They should be asked to test samples for which the result is known. These may be reference materials or simply some samples which have already been tested.

• The results are recorded and evaluated to establish that competence has been maintained. A report should be included in the staff member’s training record and retraining organised if necessary.

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Issues of Consistency of Evaluation of Test Results

Colour Vision

All staff recruited for textile or leather testing should be screened for colour vision defects. The Ishihara colour blindness charts can be purchased and the test carried out in house. Alternatively potential staff can be referred to an optician. Any staff with colour vision defects will, manifestly, not be able to be deployed in colour matching or grey scale assessments which will restrict flexibility of deployment. Clearly this will need to be considered in any recruitments. It is strongly advised that a colour blindness test be carried out at the interview stage for new staff so this can be factored into any decisions on recruitment.

Regular Checks on Consistency in Evaluations

Many leather and textile related tests involve the assessment of colour changes in samples or transfer of staining to reference cloths using a grey scale. Increasingly laboratories use computerised equipment to provide more objective assessments but such instrumentation is still expensive and many laboratories still rely on assessments carried out visually. Clearly any such system can be prone to an element of subjectivity especially in half or quarter unit interpolated grey index evaluations. Similar issues arise in the case of tests such as pilling where evaluations against standard photographs are involved.

Proficiency testing results, especially trends over time, will reveal any significant bias in the performance of the laboratory as a whole but there should also be in-house evaluations of consistency of data between staff and over time.

Once every three months all staff authorised for a test should be asked to independently assess the same three samples. They need not necessarily all carry out the complete test but only the final grey scale or similar assessment. The samples chosen can be prepared specially or can simply be real samples retained from normal running. The three should cover the normal range expected for real samples.

The results will, inevitably show some variation. This does not necessarily mean that some staff are obtaining wrong results but is simply a reflection of the nature of the measurement.

Data should be recorded and retained as part of the staff competence and quality control records. It should be analysed as follows.

• Identify any major deviations for a specific staff member in the current round of checks. Formal statistical evaluation is not appropriate unless at least seven staff members participate. In this case a mean and standard deviation can be calculated. Any data outside two standard deviations should be taken up with the staff member concerned in order to identify the reason for their evaluation. In most cases a simple scrutiny of the data will reveal any blatant deviations from the consensus.

   

• The data should be assessed for trends over time. A graphical representation is often revealing. If the results for each staff member are plotted against time then it will be clearly apparent if any evaluators show a tendency to consistently higher or lower assessments.

   

The objective is to ensure reasonably consistent assessments, irrespective of which operator conducts the test. Any anomalies in this regard should be dealt with by discussion with staff and retraining exercises as necessary.

The data above is for one year of comparisons for three technicians carrying out greyscale evaluations on three typical samples every three months. Note that although it is conventional for staff to record interpolated evaluations as, for example, 3/3.5, such a reading should be quantified as 3.25 for the purpose of this exercise. The graph clearly brings out that Technician A consistently reports slightly higher estimates than the other two. Technicians B and C show no particular performance difference. Below is shown some records of staff evaluation for a range of fastness tests. To the right is an example of the raw data generated by one staff member. To reinforce the record the fabric samples and stain transfer cloth have been retained.