I agree that the 1994 legislation has implications for designers of glass facades; it places an obligation on those designers to consider how such structures will be maintained and kept clean. However, the actual emphasis and aim of the legislation is for designers to consider how buildings will be maintained and cleaned safely.
The 1994 CDM regulations were the first to place responsibilities on designers, which includes both engineers and architects, to consider and identify how the health and safety of persons may be affected by their designs; not only during the construction of the structure, but also in the use and maintenance of that structure. Any risks identified are required to be, at best, eliminated, or, if avoidance is not possible, mitigated.
I suspect the general public is mostly unaware of the abundance of safety legislation and the genuine effort and drive to avoid accidents that prevails throughout the construction industry.
How to clean a building is not the major problem. How to clean it safely is.