The state of practice in Canada, as described in the literature, concerning ventilation, air distribution and air quality in warehouses and light industrial buildings is reviewed. There is little documented field information available. Modelling processes have not been developed which can provide thenecessary detail. Measurement of air flows, both in the field and in models, is difficult. The regulatory environment in Canada allows considerable innovation in developing conservation procedures.
Investigations have been carried out over the last three years in industrial buildings having a variety of manufacturing processes. Data were collected on contaminant source and behaviour, exhaust ventilation, supply air, workroom pressure differentials, air currents in the workroom and discharges from exhaust ventilation systems. From these measurements a workroom air balance was drawn up and the re-entrainment of contamination from discharge into the breathing zone of people in the workroom was studied.
Natural ventilation has a specific significance in creating a tolerable environment in manufacturing plants with high technological heat loads. Equations for the calculation of natural ventilation for single storey industrial halls are derived from the mesh procedure, as well as other solutions for other buildings. Guidelines are given for the draught-free introduction of supply air. Reference is made to other design possibilities for the natural ventilation of buildings.
Ventilation and air exchange in buildings and industrial plants can be induced by external winds and by buoyancy forces. The dependence of the air exchange and heat transfer on a large number of factors, including the detailed configuration of the building and surroundings makes an analytical or numerical analysis of practical design problems impractical, particularly when both the buoyancy and the wind-induced pressures are of the same order of magnitude.
Ventilation efficiency was measured with freon gas in 3 large industrial buildings under normal working conditions. Size of building varied from 3000 to 10000 m2 and room height from 5-19 m. The ventilation systems were of 3 types: 1. Overhead fresh air supply network with conventional air inlets, 2. Fresh air supply direct to occupied zones by a low impulse system, and 3. Overhead fresh air supply distributed by the Dirivent system. Describes techniques of tracer gas measurements. Illustrates some results in graphs.
A tracer method was developed for the evaluation of workplace ventilation. Nitrous oxide or freon was used as the tracer. The concentration of the tracer gas was measured with an infra-red analyser. The versatility of the tracer technique for industrial hygiene applications was improved by the use of a microcomputer for data calculation, display and storage. Three applications are presented: 1. determination of the capture efficiency of a local exhaust hood, 2. the evaluation of the air leakage of a room, and 3. measurement of the local ventilation rates in a large industrial plant.
A pilot study was conducted using workers from a semiconductor plant. Describes the methods used to acquire and evaluate air pollution exposure data for significant environments (including workplace, in-transit, and residence) to which workers are exposed throughout a typical 24-hour day. Summer andwinter measurements were made on products of combustion, radon, respirable particulates, and a variety of organic compounds including methylene chloride.
In discussion of air infiltration, we must consider air leakage flow, air change, air changes per hour at 50Pa, the surface permeability coefficient, the component permeability coefficient and equivalent leakage area. Air change and air leakage data are given for multiple family houses, single family houses, offices, industrial buildings and single cell elements.
Login