Ventilation and Particulate Matter Removal System

A method for removing particulate matter from an enclosure having an internal space and an opening into the internal space, comprising the steps of:

• positioning a cover adjacent the opening so that the cover covers the opening;
• providing a gas source external to the internal space;
• providing an inlet conduit that in use extends through the cover and is adapted to direct gas from the gas source to at least one gas outlet within the internal space whereby particulate matter within the internal space is dislodged and entrained in gas within the internal space;
• providing a source of partial vacuum adapted to maintain a partial vacuum within the enclosed space and to draw gas and particulate matter entrained therein from the internal space firstly through an outlet conduit and then through a particulate matter separation means comprising at least one filter;
• providing a sensor for sensing concentration of particulate matter in gas leaving the enclosed space;
• and
• using the sensor to derive and provide to a user information on concentration of particulate matter leaving the internal space;
• the user using gas from the gas source to dislodge particulate matter in the internal space until a satisfactory value of the concentration is achieved.