Ergomonics along with risk factor assessment and intervention and decrease the risk of injury/illness, enhance worker productivity and improve quality of work life. This is often accomplished by ergonomistic (information about people (height, weight, their ability to handle information and make decisions, their ability to see and hear and their ability to work in extremes of temperature) with individual risk factors to make the workplace safe, comfortable, and more productive. An ergonomist studies the way that these things vary in a group of people. With this information the ergonomist, working with designers and engineers, ensures that a product or service will be able to be used comfortably, efficiently and safely. This design must be for a wide range of people who use the product - including children, the elderly and the disabled when applicable. An ergonomist can also assess existing products and services; showing where they fail to 'fit' the user (in every sense of the word) and suggesting how this fit may be improved.