42 Plant process diagnostic services for detecting leakage, blockage, carry-over flow rate variation, channeling density variation and other plant performance problems; consultation services, namely, providing advice and technical information relating to the purification of gases, liquids, natural gas, industrial oils, petrochemicals and catalysts; providing advice and technical information relating to the use of catalysts in the production of nitric acid and in the manufacture of hydrocyanic acid, prussic acid and Hydrogen Cyanide; chemical plant operation services; providing consultancy and technical information relating to the provision, installation, operation and disposal of chemical catalysts