DISINFECTANTS VS. SANITIZERS

 

Questions arise as to the difference between a "Disinfectant" and a "Sanitizer".  The important principle to recognize is that our technical brochures contain both "disinfectant" and "sanitizer" information so users may have the data needed for their specific applications.

 

          Hospitals are mainly interested in "disinfectant" data.

 

          Food service related industries guided by the Public Health Services are primarily concerned with "sanitizer" claims.

 

The actual difference between the two terms is, to some extent, a matter of legal definition.  In current American regulatory parlance:

 

          A Disinfectant is a product which completely destroys all specific test organisms in 10 minutes under conditions of the AOAC Use Dilution Test.

 

          A Sanitizer is a product which destroys 99.999% of specified test bacteria in 30 seconds under conditions of the Official Detergent Sanitizer Test (sometimes called Weber & Black Test).

 

Obviously, the two tests deal with different aspects of the same problem - killing bacteria.  It seems reasonable that there should be some basis for using them interchangeably.  The law, however does not at this time permit such interchange.  The history of germicide usage does not necessarily justify this restriction, but it explains how it came about.

 

Use of germicides to aid infection control was pioneered by hospitals in the 19th century.  Interest centered on completely destroying all possible microorganisms.  In the normal course of hospital application it was felt practical to allow at least ten minutes of contact time to accomplish this objective.  As a result, most disinfectant tests were developed to as certain whether any bacteria survived ten minutes of germicide contact - nothing more, nothing less.  As a matter of fact, when contact times significantly less than ten minutes are allowed, it becomes very difficult to get any kind of meaningful results out of the Use Dilution Test.

 

In food service and other public health related industries, interest in germicides appeared much later than in the hospitals.  When interest did arise, it became obvious that the conditions of use were different than in hospitals and that tests based on ten minutes contact time could not be satisfactorily interpreted.

 

The classic illustration of the problem is provided by the bartender who washes a used drinking glass, rinses it, plunges it momentarily into a germicide solution and sets it on rack for reuse.  The Public Health related professionals reasoned that in many cases 30 seconds was about all the contact time they could realistically expect.  But the prevailing disinfectant tests could not yield 30 second results.   So they developed their own test - which is now the Official Detergent Sanitizer Test.

 

The Public Health scientists did not anticipate that they could actually get complete kill in 30 seconds with any practical chemical agent.  So they developed a test in which bacteria are actually counted (as opposed to the Use Dilution Test which indicates presence of bacteria but yields no counts).  They found through many trials that they actually could get 99.999% reductions in 30 seconds with practical agents; they reasoned that this was a very acceptable, if not a perfect, standard; they adopted 99.999% reduction in 30 seconds as the test criterion for accepting germicides in their particular application.  They called such products Sanitizers.