The amount of time a trainer can spend in front of a class depends on many factors such as the difficulty of the course and the number of different courses that the trainer has to train.
I suppose it would be possible for trainers to spend 100 per cent of their time in the classroom if they have full administrative support and the courses always fill a complete week (it is difficult to schedule courses without any gaps between them).
Eventually fatigue, with a corresponding decline in standards, will set in. If you have to support a massive training effort, and your trainers are committed to the programme, it is possible to sustain a face-to-face ratio of 80 per cent.
More realistically you would expect trainers to spend some of their time on preparation, administration, revision of existing materials and development of new materials. The proportion of the times spent on these activities will vary depending where the trainers are on their career development.
Rule of thumb: You would normally expect trainers to have a face-to-face ratio of 50 per cent.
This is supported by data from several benchmarking exercises I carried out with a number of companies.
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