Is Henry?s Law Constant? A Review of Its Description in Environmental Engineering Texts

  • John W Duggan


A survey of how Henry?s Law is cited in a wide range of texts suggests that there is significant variation in the presentation of the definition, breadth of theory, applications and limitations of this relationship in technical resources used by students. This is of importance because students and practitioners must be able to evaluate and apply the theory of engineering principles in order to effectively design and model environmental systems. Critical design errors may result from incomplete or inaccurate explanations of a principle in a technical resource. Most topic-specific texts provided detailed descriptions of Henry?s Law. The presentation of Henry?s Law in more general environmental engineering texts and other technical resources provided less detailed descriptions. In many cases the theory and application of Henry?s Law appear to have been oversimplified. This paper reviews the descriptions of Henry?s Law in texts and other resources to demonstrate potential effects on student learning and professional practice that may result from oversimplifications of this engineering principle.