A firing range where the contaminent was lead dust and unburnt propellant. failed its insurance inspections. They contacted Compliance LEV to assess the system. 
We found that there was more air being pushed into the range than was being drawn out, this meant that the room became charged with a positive pressure and the result was very turbulent air which actually flowed backwards in the room instead of the desired direction.
Our P604 design engineers worked on a LEV solution meeting HSG254 guidance and COSHH regulations.
Result – LEV system designed, installed and fully compliant.