Some advice and a bit of a rant....Most people (unless trained in environmental engineering) don't realize some of the hazards involved in home restoration or how to protect themselves. The one I'm going to touch on today is the one causing us a headache at the moment. Anytime you hire a contractor to do any sort of concrete work there is a chance that toxic silica dust could be in your home (if they don't do their job correctly). Concrete, quartz, marble, stone, terrazzo, etc...contain crystalline silica. When those materials are ground, cut, drilled or disturbed....silica dust occurs. (That is why you should always mix thinset/mortar outside, as well as do all of your cutting outside as well!)
Per OSHA "Crystalline silica has been classified as a human lung carcinogen. Additionally, breathing crystalline silica dust can cause silicosis, which in severe cases can be disabling, or even fatal. The respirable silica dust enters the lungs and causes the formation of scar tissue, thus reducing the lungs’ ability to take in oxygen. There is no cure for silicosis. Since silicosis affects lung function, it makes one more susceptible to lung infections like tuberculosis."
It only takes a very small amount of airborne silica dust to create a health hazard. It can also cause chronic kidney disease and end stage renal failure.
As stated previously, we prefer to do all the work ourselves - that way we know it's done correctly. I can't tell you how many times we have gone into a home where the homeowner had hired a contractor for "x", and when we rip it out we discover the contractor did not do the job correctly or did a basic "cover up" job. I'm not saying all contractors are bad, there are some really good ones out there - but definitely do your homework.
In our case, with the terrazzo floors - we had no choice but to hire someone who specialized and is certified in terrazzo. The contractor we went with had 4 generations of experience, had been in business since the 1920s and did most all the terrazzo floors for all the schools and hospitals in the area. They were licensed and insured and were only 1 of 2 contractors in the state certified for terrazzo. Needless to say, we felt pretty good about their ability to polish our floors.
We have never been so wrong. They did not do anything they should have. They did not contain their work area, they did not turn off the HVAC, nor block any vents/returns. They left trash all over our home. The main kicker is they ruined literally everything we own. The terrazzo was located on only 1 floor of the home but there is a large coating of toxic silica dust on all 4 floors due to them not covering vents or turning off the HVAC. Every single item we own had to be thrown out or cleaned by an environmental company. All electronics - trash. Mattresses, furniture, etc...trash....not to mention the entire HVAC system, which we just upgraded the week before, is now toast and will need to be replaced. Needless to say we are in the middle of a nightmare. The kicker to all of this, is the company who grinds silica (terrazzo) for a living and who has done so since the 1920s has an exclusion in their policy which states they are not insured for silica dust. Aka - We will get no compensation for any of this without pursuing via the legal system.
I am sharing our story for 2 reasons: To make people aware that no matter how much you "look into" the people you hire, unless you specifically request to see their insurance policy and can think of absolutely everything that could go wrong - there are no safeguards. The other reason is that most people would not even know they couldn't enter their home with the dust everywhere. Most people don't know about silica and the health hazards involved. Most people would vacuum it up or clean it up as best they could and move on, however they are gambling with their life. Silica is just as toxic as asbestos and just as damaging to the human body.
We would like to think we have a leg up when hiring contractors....but sometimes....people just suck.