Many producers of powders or dusts have the potential risk of dust explosion if a combination of a series of events occur at the same time. The first stage of establishing if there is a risk is to test samples of dust from various parts of the process that are considered as risk zones. It is well documented that more than 70 % of dusts produced in today's industrial processes are combustible. Once the explosion characteristics of the powder or dust have been determined, the areas where ignition sources can be produced and where ignition of a dust cloud could occur (Risk Zone) should be evaluated. There are measures taken today by industry to prevent primary and secondary explosions. Good housekeeping usually minimises the effect mostly of a secondary explosion, however risk analysis, plant layout, design and implementation of modern explosion prevention and protection equipment should be considered at the feasibility stage of the project. Existing plants without this measure could face severe financial losses or legal action in the event of a dust explosion resulting from negligence or ignorance of plant owners. This paper summarises the application of the following technologies with specific detail on the application of Long Wave Infra Red technology prevention systems using: 1. EXPLOSION PREVENTION -. (A) Friction particles, glowing ember and spark detection with extinguishing or ignition isolation systems - prevention of ignition by early detection of non electrical ignition sources in processes from 400 Deg C which is below the minimum ignition temperature (M.I.T) of most dusts (B) Inerting systems with or by limiting the oxygen concentration by inerting 2. EXPLOSION PROTECTION (A) Explosion Vents, Doors and Diverters upon ignition the pressure may be relieved and the fireball directed to a safe area. (B) Explosion suppression and Isolation if indoors or the release of combustible by products to atmosphere is undesirable, then the pressure rise can be detected and the combustion process stopped by use of an approved suppressant and isolated from propagating to adjoining equipment. (C) Containment - ensuring the structural strength is adequate to cope with the impact of a dust explosion.
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