surface or cause

surface or cause panels to fall out of the framework. Ceilings may be badly stained, be old or have poor quality surfaces, therefore do not use any other chemicals other than the chemical stipulated, as this may strip the surface or leave streaky marks. If any panels are damaged or fall out during cleaning immediately inform the Supervisor.
7  Operatives to spray chemical on to an area of approx. 1m2 and allow to soak for a few minutes. Repeat this process in a methodical manner working across the ceiling. Operatives to take care when cleaning false ceilings to clean right up to and including edges of support framework. Note: do not over spray as this will cause streaky marks and drip on to the floor.
8  Operatives to use a clean cloth or ‘Greenie’ (if the surface allows) to wash each area in turn, an extension pole with cloth or ‘Greenie’ fitted may be used if necessary.
9  On completion of cleaning, operatives to dispose of all waste chemicals and materials on site and remove all cleaning equipment, chemicals and signage to company vehicle.
10  Operatives are not to leave the site until authorised by Supervisor.

demand is being

demand is being addressed by firms who market air duct cleaning services. Because barriers to entering the air duct cleaning business are minimal and uniform standards of professional practice have yet to be adopted, anyone with an interest can enter the field. This has permitted firms to spring up with controversial techniques. This is not to say that most duct cleaning businesses are unethical. Companies are seeking the best solutions for each individual home with contamination problems. They are looking for new and better ways to serve a very troubled clientele. The clientele is also wary because little is known about duct cleaning. What is the best source of information for consumers about air duct cleaning? Unfortunately, since there are few or no published papers by independent researchers, most of the information available is from people associated with the air duct cleaning industry. Since air duct cleaning procedures have evolved mostly from trial and error as unique and creative solutions have been sought, there has been considerable confusion in the minds of consumers who fear or who are experiencing indoor air quality problems. Here are some insights gleaned from a publication, Indoor Air Review1. The articles have all been written by people involved with firms specializing in air duct cleaning, filtration, and consulting.

TESTING METHODS AND EQUIPMENT

TESTING METHODS AND EQUIPMENT There are two main methods of testing. The pressurization subtraction method utilizes a pressurization unit (i.e. a high-powered fan set up in a doorway and connected to pressure gauges) to pressurize first the entire space that is heated and/or cooled and then the same space with the duct system blocked off. This method is less accurate than the duct testing method. The duct testing method uses a calibrated fan that gently pressurizes the ducts and measures the airflow through the ducts to indicate total leakage. The duct tester consists of a portable fan with calibrated digital pressure gauges that is connected at the blower compartment of the air handler, or attached to the main return grill. All of the duct registers and grills are temporarily sealed, and the duct tester fan is turned on to pressurize the system. The fan pressure is read from the gauges and converted to an equivalent duct leakage rate in cubic feet per minute (cfm). If the amount of air loss falls outside acceptable limits, sealing will be required to correct the condition. This method of testing is preferred, because it measures low airflow accurately, and simulates what takes place under normal operating conditions.