Maths has never been my strongest subject so I hope someone can assist on this;
A client has had a clean air solutions company come in and leave monitoring devices around the production areas for 24 hours to sample the dust quantity in the air. Instead of using the HSE mg/m3 approach they have instead used µg/m3. In their report they have stated;
The highest reading over the 24 hours peaked at around 1630 µg/m3 however the average was 61 µg/m3.All particles in the range of 0.1-10.0 micrometer (µm) (1 µm = 1/1000 mm) are airborne particles. The most hazardous and harmful particles are the breathable and respirable particles in the range of 0.1-10.0 µm. Those are measured and the result is shown in µg/m3.
If I am not mistaken, they have used microgram readings instead of milligram readings so therefore the average is 0.0061 mg/m3 which is well within the work exposure limits? The company works with card and paper that does generate small amounts of dust however these are all pre-cut and supplied by the supplier. Weekly housekeeping is carried out and daily spot cleans to keep the site clean.
Have I translated the micrograms to milligrams correctly and should further action be taken? According to the report the company that did the testing suggested they had units installed costing £800 p/m to ensure cleaner air.