English

Natural ventilation of mill buildings is a process which is complicated by several factors such as external wind pressure and local distribution of heat sources. Describes theoretical and small-scale physical modelling techniques for predicting ventilation rates. The theoretical approach using a computer for the numerical aspects allows rapid and reliable assessment of the ventilation rates for very complicated building designs under any appropriate wind conditions.

Lists the HOTCAN computer program devised for use in the Division of Building Research (NRC) program on low energy houses. It is written in BASIC and is capable of estimating the space heating requirements of residences. Gives basic equations and assumptions, and weather data required, along with a listing of the program and a sample run.

Reviews technical progress being made in the industrial ventilation field by different investigators through out the world. Subjects reviewed and updated include natural ventilation, local exhaust ventilation, specialised ventilation techniques (dilution, air jets, air curtains, recirculation of filtered air, tracers for ventilation studies) and mine ventilation. Presents typical applications of the new technology to solving industrial ventilation problems, and identifies areas requiring further research and development.

Identifies alternative methods available to control indoor air pollutant exposures. Describes the performance characteristics of ventilation systems and of air cleaning devices used in mixed modes for ventilation of occupied spaces. Reviews models for predicting effectiveness of several alternative modes, with field trial validation results cited where available. Briefly reviews previous confined-space studies as points of departure for consideration of necessary air quality, ventilation and air cleaning.

Describes a test carried out in the Fridley, MN, Junior High School Music Dept. to obtain air quality, energy and subjective response data on an Automatic Variable Ventilation System. Devises a control system with both CO2 and temperature inputs to control the use of outdoor air. Infiltration measurements lead to a quantitative measure of ventilation efficiency, which in turn lead to recommendations for air circulation patterns in rooms. The measured ventilation efficiency enables energy and CO2 models to fit measured data. Finds energy savings of approx. 20% in this application.

Shows the usefulness of a model for extrapolating environmental chamber results on pollutant emissions from combustion appliances to determine indoor pollutant concentrations in actual residences. Investigates the effects of infiltration, whole-house ventilation, and spot ventilation on pollutant levels. Results show that a range hood is the most effective means of removing pollutants emitted from a gas-fired range; removal rates vary from 60%-87%.

Carries out measurements of indoor atmospheric environment in a day nursery and a kindergarten in Denmark, where natural air infiltration supplies the room with only 1-2 m3 fresh air per person and hour under the prescribed occupancy. Duplicates situation under controlled conditions in a climate chamber. Results indicate unacceptably high concentrations of carbon-dioxide, and show the need for more elaborate building design in airtight buildings.

Discusses 2 reports by the Agrement Board which indicate that insulated doors in busy industrial buildings such as warehouses do not save much energy. Further studies by the Bolton Gate co. show that the addition of a plastic strip curtain gives significant savings. When a door is open for 5 mins perhour, the mean saving can be 15% depending on outside temperature and the air leakage of the curtain. When the door is open for 15 mins per hour, the mean saving can be 29%. States that it is easier to use plastic strip curtains with horizontal folding shutters than with doors.

States that draughtproofing doors and windows in industrial and commercial buildings offers the quickest payback of any energy conservation measure. Describes potential sources of leaks, such as ill-fitting entrance doors, and the types of material needed in draughtproofing industrial buildings according to durability and application.

Describes a computer program, Harmon, developed for the simulation of the thermal response of buildings (based on BRE's "admittance procedure") which can be used on mini-computers and utilized at the sketch design stage for the comparative evaluation of alternative designs. Gives an account of the validation exercises completed and outlines further intended refinements.