ABSTRACT
The surface should be washed with an alkali surfactant and rinsed with clean water to remove oils and greases that may have accumulated before any pretreatment is performed. The most commonly used blasting technique is dry abrasive blasting, where the velocity of the blasting particles is controlled by the pressure of compressed air. The wet abrasive blasting and hydrojet blasting offers the possibility to vary the velocity by changing water pressure. By-product abrasives can be used to remove mill scale on new constructions or rust and old paint in maintenance jobs. Manufactured abrasives are more costly than by-product slags, usually by an order of magnitude. This chapter briefly describes dry blasting with solid carbon dioxide, dry blasting with an ice abrasive, and wet blasting with soda as an abrasive. It then discusses: what silicosis is, what forms of silicon cause silicosis, low-free-silica abrasive options and hygienic measures to prevent silicosis.
