In 1924 the Institution of Chemical Engineers adopted the following definition 'A chemical engineer is a professional man experienced in the design, construction and operation of plant and works in which matter undergoes a change of state and composition.' (The first female member joined in 1942.)
As can be seen from the later definition, the occupation is not limited to the chemical industry, but more generally the process industries, or other situations in which complex physical and/or chemical processes are to be managed.
In 1951 the President of the Institution of Chemical Engineers said in his Presidential Address "I believe most of us would be willing to regard Edward Charles Howard (1774-1816) as the first chemical engineer of any eminence. Others have suggested Johann Rudolf Glauber (1604-1670) for his development of processes for the manufacture of the major industrial acids.
The current definition of Chemical Engineering is "the profession in which knowledge of mathematics, physics, chemistry and biology, gained by study, experience, and practice, is applied with judgment to develop economic and safe ways of using materials to benefit mankind."
Historically, the chemical engineer has been primarily concerned with process engineering. The modern discipline of chemical engineering, however, encompasses much more than just process engineering. Chemical engineers are now engaged in the development and production of a diverse range of products, as well as in commodity and specialty chemicals. These products include high performance materials needed for aerospace, automotive, biomedical, electronic, environmental and military applications. Examples include ultra-strong fibers, fabrics, adhesives and composites for vehicles, bio-compatible materials for implants and prosthetics, gels for medical applications, pharmaceuticals, and films with special dielectric, optical or spectroscopic properties for opto-electronic devices. Additionally, chemical engineering is often intertwined with biology and biomedical engineering. Many chemical engineers work on biological projects such as understanding biopolymers (proteins) and mapping the human genome.
In the United States of America, the Department of Labor estimated in 2006 the number of chemical engineers to be 30,000. The average hourly wage for a chemical engineer was $39.23 per hour, but ranged from $24.07 to $57.05 per hour. The median annual salary for a chemical engineer was $78,860, with the middle 80 percent of chemical engineers making between $50,060 and $118,670 annually. Chemical engineering has been cited as the highest-paying degree for first employment of college graduates. Subsequently, a high-end salary grade is common to this profession in the USA.
In the UK, the Institution of Chemical Engineers 2006 Salary Survey reported an average over £53,000, with a starting salary for a graduate averaging £24,000.