It seems like only yesterday that I first saw abrasive media blasting in use on an architectural restoration job – a fire-damaged, limestone church in central Illinois.  I don’t remember all of the circumstances (that was over 18 years ago), but I do remember what happened.  It was a chilly morning, with a bright yellow sun – a perfect day for media blasting – cool, dry and (based on my very positive recollections) probably a Friday to boot.  The church’s exterior seemed to glow in the morning rays.  Inside the proud historical structure, over 75 years old at the time, was very different.  The limestone in the attic area was blackened by soot from a recent fire.

The restoration contractor had seen our baking soda blasting process at a tradeshow, or possibly advertised in a trade magazine.  The demonstration was not just a “dog and pony show”, but a last ditch effort after many other methods were eliminated, like painting over the soot to cover it, or had failed, like chemical cleaning and pressure washing to name a few. Everyone on the site had high hopes – the general contractor, the insurance adjuster, the church deacon, and a very young, abrasive blasting salesman – that the modified “sand-blasting” machine shooting sodium bicarbonate, or baking soda, with compressed air would clean the soot and charring without damage to the beautiful, nearly white limestone.  (See picture #1)  Although the picture is quite old, and pixelated – just like my own memory of that day,  it still shows clearly the “before” and “after” results of that trial.