Macquorn Rankine Forrester, Sr. 
May 5, 1933 - April 20, 2016

The Intoximeters family and the Breath Alcohol Testing industry recently lost one of its pioneers. 

In memory of Macquorn "Mac" Forrester:


The first breath alcohol testing instrument (The Drunkometer) was developed by Dr. Rolla N. Harger in 1938. In 1941, the Intoximeter was invented by Dr. Glenn C. Forrester. This device was closely followed by the Alcometer, which was invented by Professor Leon Greenberg. All of the breath collection devices were designed to measure breath alcohol concentrations that were related back to blood alcohol concentrations.

In 1954, Robert Borkenstein, an officer with the Indiana State Police, invented the Breathalyzer.

Breathalyzer breath testing instruments were originally manufactured and sold by the Stevenson Chemical Corporation of Red Bank, New Jersey. The rights to such instruments were subsequently acquired by the Smith and Wesson Electronics Company of Springfield, Massachusetts, which manufactured and through its mature law enforcement distribution channel successfully sold the Breathalyzer until 1984.  Due to this success,“Breathalyzer” earned the most recognized name in the industry.

In 1959, Mac Forrester took the helm at Intoximeters, Inc. from his father (Dr. Glenn Forrester).  Breath alcohol testing instrumentation was a fledgling industry and Intoximeters competed directly with its Photo Electronic Intoximeters (PEI) against the industry leading Breathalyzer. 

Unlike his father, who was more of a scientist than businessman, Mac was prepared to use both his science background and his Harvard business school training to build a business that would lead the breath test instrument industry for the next six decades.

Mac drove innovation in the industry.  He was responsible for developing:

  • The first Gas Chromatograph breath alcohol analyzer (GCI),
  • The first evidential fuel cell based instrument; the Auto-Intoximeter (Auto I), 
  • The first infrared based breath alcohol instrument with an integrated computer for data entry (Intoximeter IR3000), 
  • The first instrument with fuel cell and infrared based analytical technologies combined (IR3000DFC), 
  • The premier line of handheld instruments, The Alco-Sensor line, which with the help of Tom Jones from Lion Labs and the engineering expertise of Karl Wolf Sr., was instrumental in defining the fuel cell based Preliminary Breath Test market, and
  • The market for dry gas calibration systems.

At the time of his death, Intoximeters, Inc. is recognized as not only the oldest but the most successful breath alcohol detection instrument manufacturer and marketer in North America; if not the world. This success is largely due to Mac’s leadership, vision and relentless work ethic.

Mac in his early years was known for his larger than life personality, his desire to impose his will on the industry and commitment to the success of his company.  Sometimes this gregariousness got Mac into trouble, but mostly it worked to his advantage.  In all cases, everyone in the industry knew Mac was a force to be reckoned with.    

In the later years Mac was less aggressive.  Mac was able to manage Intoximeters such that it earned and maintains a reputation for providing a highest level of customer service, it has the premier sales force in the industry, it has a commitment to excellence and is the leader in innovation in the industry.

Mac’s legacy will be his company, the imprint he made on all of the employees that worked with him, and all of the relationships he built through the business, his personal friends and his family. 

He will be sorely missed.