text: **Physical health risks**can be caused by a**variety of circumstances and exposures**or by**inadequate**
  **ergonomics**. Natural**circumstances**at work can pose such health risks, that is, temperature, storms 
  and floods, unsafe terrain, biological agents and so on; or the risks are due to manmade circumstances, 
  that is, work in buildings, on roofs and towers, on traffic routes, under artificial ventilation.**Exposure**is 
  a general term to describe the interaction between environment / emissions / contaminants and the 
  human organism. In a workplace context, ‘exposure’ mainly covers emissions from machinery or from 
  tools and materials, for example, noise, vibration, dust, electromagnetic fields and chemical substances. 
  
  Risks from**inadequate ergonomics**harm in particular the musculoskeletal system. Ergonomic risks of 
  manual work are typically caused by repetitive hand and arm movements, tiring positions, for example, 
  permanent kneeling or overhead work, lifting and moving of heavy loads, or of patients and so on. A 
  certain ergonomic risk is**physical inactivity**, in practice sitting most of the working time. Not only 
  administrative tasks but also many occupations in service or industry require permanent sitting, for 
  example, drivers, cashiers, part assembly operators and so on (often called ‘sedentary occupations’). 