Mill Hill Quarries Air Monitoring
Mill Hill Quarries Ltd. operates slate quarries in Devon and Cornwall, producing some of the only Cornish roof slate in the region. The process of splitting roofing slate can produce dust and respirable crystalline silica, which can be hazardous to health. Following extensive investment by the company into local exhaust ventilation, CLAW were engaged by Mill Hill Quarries Ltd. to investigate the effectiveness of the new ventilation system.
CLAW designed and carried out an indoor air quality monitoring programme tailored to accommodate the busy production processes of the quarry. Specialist personal sampling equipment was selected to accurately monitor staff exposure in a convenient way that didnít disrupt daily working practices or staff carrying out their daily duties. Dust monitoring was followed up by laboratory analysis to gain a precise understanding of airborne pollutants in the production area. Analysis of the dust combined with a review of staff work diaries allowed CLAW to pinpoint areas of excessive pollutants. This enabled the quarry to identify best practice working procedures to ensure local exhaust ventilation is used correctly and effectively.
Staff received in house training in these best practice procedures. Following this the site was successfully resampled to verify that this translated to a measurable improvement in air quality that met Health and Safety Executive (HSE) safe targets.
Through evidence that levels of hazardous air pollutants are consistently better than minimum HSE standards Mill Hill Quarries Ltd. are now confident their working practices and equipment effectively reduces the impact of dust on staff to levels below those set out by the HSE.