She emerged on the list in 2008, when she gained total control of the company after her husband, Ken, died in a freak constructionaccident at their Wisconsin home.
Esa member-states considered its polar ice measurements to be so important to the assessment of climate change that they approved the construction of a facsimile spacecraft within months of the accident.
Businesses will only face health and safety inspections if they are operating in areas deemed to be higher-risk, such as construction and food production, or if they have had an accident or a track record of poor performance.