Protecting against dreaded dust
I get asked many questions about floor sanding but recently I was consulted about the dangers of sanding a particular type of timber floor. The client whose floor it was had mentioned to the contractor that the wood in question was known to cause health issues when sanded. There was no mention of what her specific issues where but of course whenever there is concern expressed about any form of dust in a health context the natural assumption is that we are talking about respiration issues and possible long term lung damage. However whilst most people are aware of these problems they are usually less aware of some of the other possibilities.
So let’s consider the 5 problems associated with wood dust and the measures that can be taken to mitigate the danger.
Lung damage
Like our old “friend” asbestos, fine wood dust can hang in the air and be breathed in. Whilst not as life threatening as asbestos this dust can cause very small wounds to the lungs which are not immediately noticeable but are irreversible and eventually diminish the lung capacity.
Irritation
This is quite common and normally manifests itself by causing itching, sneezing, short term breathing problems, skin flushing, runny nose etc. Merbau, Ipe and Iroko are timbers regularly used in flooring that can commonly cause many of the above symptoms, although just about every timber is listed as an irritant at some level.
Sensitivity
Some woods become more sensitive to us with repeated exposure. In other words we react a little worse to them with each subsequent contact. Iroko is a timber which is listed as a sensitiser whilst the Merbau and Ipe are not
Toxicity
Some timbers are considered to be directly toxic, fortunately for us none of those listed in the wood toxicity and allergen chart are in common use for flooring!
Cancer Causing
In this instance we are referring to nasal cancer that can occur as a direct result of exposure to the dust from specific timbers. These cancers can affect any of the passages around the upper respiratory tract including the throat and unfortunately there are several timbers that can be used in flooring on the database including walnut and oak. Although it is rare, there is one very well-known case involving a prominent member of the floor sanding community.
Having listed the dangers of wood dust let’s talk about what we can do to minimise the risk.
The most obvious control measure is to create as little airborne dust as possible. Since one of the best methods of achieving this (water), is ruled out by nature of the surface we are working on, it is essential that anyone regularly floor sanding uses only professional sanding equipment which has far better dust control than the cheap hire sanders. Smaller machines such as edgers and random orbital sanders can be improved by hooking them up to extractors and it is possible to get DCS (dust control systems) for belt sanders but in my experience they add little or nothing to the performance of professional machines.
Strategically placed air movers used in a room with open windows can suck the old, stale air from the room allowing fresh air to replace it. This is particularly useful in larger areas with a door to the outside and is often overlooked.
Personal protection equipment such as masks or better still respirators should be worn all the time if using cheaper hire machines and would be recommended by some health experts as essential the whole time. With regard to irritation, it is obviously impossible to cover every piece skin but a respirator will help and if sanding a timber that you are particular sensitive to, a Tyvek suit and gloves can be used.
Update to blog
Since the time of writing the situation has changed regarding our understanding of PPE (personal protective equipment). It is now advised that all skin is covered, Tyvek suits are worn and disposed of at end of working period and full face fitted masks are now obligatory.
Modern floor sanding equipment (when well maintained) is incredibly efficient at dust control. However, the greatest exposure to dust, irrespective of the quality of the machines, is during the emptying of dust bags. If you find it impossible to work using any form of protection, I would strongly suggest that you use it at this point if no other.
A list of timbers and the risks associated with them can be found online at The Wood Database to whom I owe thanks for most of the information shown above.