Our company on occasion has to cut masonry products whilst on site, we have looked at several ways of combating this including off site cutting, clipper saws usage in controled cutting zones/areas, the use of block splitters, and finally the use of stihl saws fitted with suppression kits (as a last resort). please note:- we have recently managed to complete projects where we have not used a stihl saw at all. wherever and whenever we wet cut we also ensure that the operative is face fit tested and wears an FFP2V filter mask, a single operative will possible cut no more that 6-8 blocks per day, and due to the suppression kit there is only a small amount of dust generated over a period of approximately 20 minutes. I am aware that the HSE guidance is now stating that FFP3 filter masks should be used when cutting silica based products but to me this seems a little excessive given that we are wet cutting and that cutting does not take place for prolonged periods, or do we need to upgrade the RPE that we are providing our operatives with? thanks in advance AL

thanks for the comments adrian, we have not undertaken any measurements, however the cutting is undertaken outdoors in well ventilated areas and as already mentioned the cutting takes place only for short duration AL

Allan, difficult to argue with HSE guidance and information without being able to quantify a reasonable approach based on accurate scientific data. As many already know silica is a fibrogenic dust (as is asbestos) which can cause pronounced fibrogenic reaction resulting in scars in the lung tissue and obvious disease (such as silicosis). I assume that you have a copy of MDHS101: Crystalline Silica in Respirable Airborne Dusts? If not get a copy. Also checkout a free HSE document: www.hse.gov.uk/pubns/guidance/g404.pdf Or contact me direct and I'll see if I can assist.

Thanks for that Gary2468 nice to see that i am not on my own with this issue. our FFP2V face filtering masks have an APF of 10 however on the latest HSE guidance its states that FFP3 should be used with an APF of 20

Q. Gary, How do you know that you have technically achieved perfect dust suppression with water?

Hi Gary, I’m glad you mention sampling. In most cases it is feasible to control respirable silica by dust suppression techniques or local exhaust ventilation. I’m sure most of us are aware of the exposure to RCS which has many adverse health effects including silicosis, chronic obstructive pulmonary disease (COPD), lung cancer and other connective tissue disorders. I assume that this analytical sampling is carried out by a competent person and that where workers may be regularly exposed to respirable crystalline silica levels greater than 0.1 g/m3, 8-hour TWA, then health surveillance including a respiratory questionnaire, lung function testing and chest X-rays are provided. The reason for mentioning this is about location (i.e. indoors/outdoors) of the task and treatment of waste water/dust particles. On many occasions this is overlooked and particulates within water are released and once dried can become airborne. This is very often forgotten about and sampling is generally done for the task only with very little in the way of reviewing post-task.

Descarte8, you are quite correct it is not a 100% effective solution – which is why I asked Gary the question on how he perceives he has achieved this. Monitoring must be carried out by competent professionals (i.e. occupational hygienists) and backed up by scientific data, this may include some health screening. Another good document relating to this subject can be obtained free from HSE: rr827(1) (health surveillance in silica exposed workers).