Case Studies » WL Duffields & Sons Ltd
Duffield’s are manufacturers of animal feeds from four strategically placed mills which are UFAS approved. The business is focused on producing feeds for the pig, poultry, cattle, sheep, game and specialist feed sectors sold directly and through the merchant trade. Production from the four plants is approximately 450,000 Te per annum.
Insurance recommendations drove the company to contact Mesh to carry out DSEAR RAs for the sites. Hazards are principally from dusts arising from storage, handling and processing of the feed grains and powders. Seed dust is combustible and may add to fire and explosion hazards within confined plant particularly. Fine dust may ignite – and give rise to potential fire and explosion hazards if present at sufficient concentration in air. Combustible dust properties require strict procedures and maintenance of key equipment to minimise life safety risk. Secondary risks around fired equipment, flammable gases, workshop solvents and transportation lubricants were also to be considered.
The solution provided
Mesh arranged to group the visits so as to be convenient to the locations, and issued the reports to a common format so as to assist the client with their corrective action planning.
An assessment of the each site was carried out in compliance with the DSEAR regulations 2002 and a number of points of significance were noted.
Adequate statutory checks are a critical requirement for relevant extraction, pressure systems and / or relief vents installed on-site. The safety of the operations relies heavily upon the operation of the dust removal and ventilation systems and the importance of PPM and inspection cannot be stressed highly enough.
Documentary evidence was provided pertaining to existing material inventory, local site procedures and maintenance - plus an overview of each site’s safety systems at the time of survey. Additional background information was provided by each site’s management team.
Hazardous Area Classification applies to those areas where a flammable atmosphere may persist either briefly or for longer periods of time as outlined in the regulations – specifically within confines of equipment or around material handling or storage locations.
The significance of earthing and continuity checks was also emphasised at the time of survey. A full review of plant operations, equipment and working procedures was undertaken to identify where potential hazardous zoning was needed and how and where sources of ignition could be removed. As well as technical measures, organizational control measures were also assessed during each visit. From the review a detailed report was presented to management with areas for improvement clearly identified in the action plan.
All of these issued were considered and detailed DSEAR reports, scenario risk assessments, hazardous zoning plans and series of recommendations was issued to management to ensure sufficient control of DSEAR risks is maintained as low as reasonably practicable (ALARP).
The regulatory guidance followed was as per BS EN 60079-10-2: Explosive Atmospheres – classification of areas – combustible dust atmospheres. Extensive Hazardous Area Classification was applied from each survey, and to support this a large number of HAC diagrams were developed and issued with the reports.