In its "Brief Description of Chemical Weapons" , The ORGANISATION FOR THE PROHIBITION OF CHEMICAL WEAPONS specifically rejects your narrow "general and traditional" interpretation of what constitutes a chemical weapon .
http://www.opcw.org/about-chemical-weapons/what-is-a-chemical-weapon/
"The general and traditional definition of a chemical weapon is a toxic chemical contained in a delivery system, such as a bomb or shell.
The Convention defines chemical weapons much more generally. The term chemical weapon is applied to any toxic chemical or its precursor that can cause death, injury, temporary incapacitation or sensory irritation through its chemical action. Munitions or other delivery devices designed to deliver chemical weapons, whether filled or unfilled, are also considered weapons themselves."

"A common conception of a chemical weapon comprises a toxic chemical contained in a delivery system such as a bomb or artillery shell. While technically correct, a definition based on this conception would only cover a small portion of the range of things the CWC prohibits as "chemical weapons". There are several reasons for the broad CWC definition, which, as described in Fact Sheet 2, includes munitions, precursor chemicals and equipment connected with production and use of chemical weapons."

For one thing, CW components—a toxic chemical and delivery system, for example— may be stored separately, each in and of itself less than a fully developed weapon. In the case of binary munitions, a nonlethal chemical may actually be stored within a munition, only to be mixed with a second chemical inserted into the munition shortly before firing, and the toxic product disseminated upon arrival at the target.