Occupational health and the analytical and numerical modeling of airflow patterns in the industrial environment

• Main Author: Pelley, Brad J.
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 2003
• Subjects: Newfoundland; Snow crab
• Online Access: https://research.library.mun.ca/11226/; https://research.library.mun.ca/11226/1/Pelley_BradJ.pdf

Possibly the world's first research on breathing problems among snow crab processing workers took place in Newfoundland in the 1970's. Preventing/mitigating these problems is of paramount importance as the snow crab industry is a major contributor to the regional economy in rural Newfoundland and Labrador communities. Crab asthma is caused by overexposure to the dusts, mists, fumes or aerosols that are generated during various processes. During these processes, proteins in the crab may become airborne and can enter the lungs and breathing tubes. A recent study suggests that very low levels of allergen will need to be achieved in crab processing plants to prevent respiratory symptoms from occurring among sensitized workers. Prior to the study described in this report, there had been no air sampling of allergen levels in snow crab processing plants in Newfoundland and Labrador. Air sampling has been carried out in four crab processing plants in Newfoundland and Labrador to identify the problematic areas. Allergen contamination concentrations have been identified and related to specific areas of the processing plants and to the individual processes themselves. -- A variety of ventilation methods have been examined with local exhausting of the workplace comprising the majority of the investigated techniques. Centerline velocity profiles for overhead, slotted, and canopy local exhaust hoods proposed in previous research have been examined. Numerical modeling of the cleaning, sawing, and batch cooling processes was carried out in both an idealistic and realistic plant domain to determine the airflow patterns in and around these individual processes, as well as determining possible capture velocities from imposed velocity profiles. Velocity profiles have been obtained for the space in the vicinity of the hood face rather than just along the centerline. Velocity and pressure contours were also determined to ascertain the degree of contaminant capture. All numerical results for idealistic and realistic plant environments ...