It is the principal representative of the nitrogen mustards because its vesicant properties are almost equal to those of HD and thus the analogy between the two types of mustard is the strongest. As a vesicant the use and production is strongly restricted within the Chemical Weapons Convention where it is classified as a Schedule 1 substance.
As the primary representative for nitrogen mustards, it shares nearly identical vesicant effects with HD, making this comparison very strong. Under the Chemical Weapons Convention, its use and production are heavily restricted, placing it in the highest-risk category (Schedule 1).