Silica in Construction: Changes to approved methods of roof tile cutting
HSE and industry stakeholders from the house building
When cutting roof tiles, workers are exposed to respirable
crystalline silica (RCS). This dust, if breathed in, causes
severe lung diseases such as silicosis. HSE have produced a video
of the effects of silicosis on people's lives.
Impact of silicosis (video)
Valley tiles are created where rooves meet (see picture). These
tiles need to be trimmed to fit. An interim agreement between
industry and HSE allowed valley tiles to be cut using hand held
power tools without wet dust suppression systems, which would
introduce additional safety hazards, such as slips.
What We Did
In order to properly assess the health risk associated with this
HSL measured RCS exposures during the cutting of valley tiles.
Cutting tiles along one valley edge took less than 10
minutes and only occurred once or twice per day. Because of this
short exposure period we used innovative
high volume respirable dust samplers to measure RCS exposures,
which would not have been possible using conventional sampling
techniques. We also used our exposure visualisation techniques (ELVIZ) system to record both real time exposure
and video of the process.
The exposure monitoring showed that if a worker cut two roof
edges of valley tiles in a shift, equating to about fifteen minutes
of work, then they would have already reached or exceeded the 8
hour time weighted average RCS exposure limit. We also demonstrated
that adjacent workers were at significant risk and that the use of
other exposure controls, such as dust masks, could be improved.
to working practice
Our findings led to a change in working practices in the
construction sector. Valley tiles are now marked up at roof level
and taken to a fixed location where they are cut whilst using
engineering controls such as water suppression.
Back to Case Studies
Back to the top