NAVIGATION. To use this work

The Layout Arrangement of this work.

For some readers this study was too large and diffuse.   It is now divided into subdivisions.

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Screen Shot 2016-03-18 at 08.41.28To remediation2T direction



This is indicated in the top menu↑.   All post are shown in the menu on the right→ .       Specialists will prefer to jump directly to their page of interest using the Right menu→.

For an overview of contents…..

Screen Shot 2016-05-16 at 18.50.05Designers are the intended readers and,  apart from some duplication, are advised to read the whole work.  This includes a large body of research and background, on spinal bio-mechanics.

Screen Shot 2016-05-17 at 15.59.14 Manufacturers can be reassured that feasibility indicates that existing components can be used , Screen Shot 2017-05-23 at 07.52.02avoiding the expense of retooling, while preserving their brand image.   Prospective manufacturers can be helped to leap ahead of the field,  ☛  →

New ideas can create both threats and opportunities , once both familiarity  and normalcy biases are overcome.  Creative disruption works.

Topics and some relevant subjects

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to architects

For New offices ‘Coolness’ is the word to  excite media interest for both the company and the Architect/Designer.   Most firms aspire to project this cutting edge image.    A 2T chair, or the derived 4M workstation, answers this exactly and in addition reduces LBP and increases productivity by lessened morbidity and stress.  Also see  ☛  PRODUCTIVITY AND WORKPLACE STRESSORS→(Article published in EurOhs, European Occupational Health and Safety Journal, Dec Dr HA Sanford)

To office managersAllows an alternative view to the usual hype, often laughably misguided, from manufacturers,


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Also of LIKELY INTEREST to a general reader

To remediationBackache & chairs.   A number of systems are described.  Spinal bio-mechanics dictates that prolonged sitting should be performed in a reclined position with frequent change of posture.  For a full remediation  a number of requirements are essential.   To be effective these are detailed in the 2 Tilt (2T) concept.

Requirements for optimising the bio-mechanics of prolonged sittingScreen Shot 2016-03-17 at 13.34.53

Partial remediations.

Partial solutionsSystems in use at present,    See ☛ Remediation→

The obvious, and perhaps only, solution was for prolonged work to be performed in a chair that has a stable, correctly supported, supine reclined mode. Shown here is the Okamura ‘Atlas’ chair.  ☛ Atlas→

Screen Shot 2013-09-29 at 14.29.22Other, commonly used partial solutions include ☛ Pelvic support→,

 ☛forward tilted seat→, & Ischial off-load →

& ☛Sit/Stand→.

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A full remediation, the 2Tilt Concept, is suggested.  See ☛ 2T concept→

Screen Shot 2016-03-12 at 16.17.49Combining these requirements can be difficult to achieve but is possible in a suitably supported reclined mode at 40-45° which conforms to spinal morphology (configuration). This alone is impractical as a work position unless a number of secondary requirements are incorporated to make this simple concept suitable and practical for a work chair.

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  1. screen-shot-2016-09-21-at-10-13-41A reclined mode for prolonged work    ☛2T reclined mode→
  2. An upright mode required for certain jobs.    ☛2T Upright mode→
  3. An unstable intermediate mode to enable a quick, easy transition between the 2T modes.    ☛2T transition mode→    ☛ dynamic seating→  With the recognition that the transition movement has physiological advantages, this has been upgraded to a ‘mode’.  The 2T now becomes a triple-mode (3M) concept.
  • A sit/stand facility can be incorporated to become a 4M version.    ☛Sit/Stand→



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‘Sitting disease’

Compared to people who sit the least, those who spend most time in a chair have a 112 % higher risk of developing diabetes, a 147% higher risk of suffering “cardiovascular events” such as strokes and a 49%t increased risk of death from any cause.  (   Alarming but not entirely an effect of the bio-mechanics and not examined here.  However some posts are relevant.