Abstract: A template buffer element with cutouts which are larger than the interior cutouts of a template, attached to the template so that ink deposited on the drawing surface is separated from the working edge of the template by the buffer element, and the cutout edges of the buffer element are separated from the place of ink deposition by the difference between the dimensions of the buffer cutouts and the template cutouts. The buffer element may be a sheet of plastic or may be an array of strips made of elastomeric or nappy material which trap an air cushion under the template so as to facilitate template movement over the drawing and provide anchorage of the template to the drawing surface when the draftsperson presses down.

Abstract: A process, for emergency use only, to exhaust smoke and gas from a fire source in the stationary structure of a building with a fan induced exhaust draft at or near the fire source. Actuation of exhaust fans at the roof of the building creates lowered air pressures in a volume of air within ducts leading to the fan inlets. This lowered air pressure in turn causes a draft of air from the building space near the fire source when a single intake to the ducts near the fire source is opened. The air velocity of the draft is sufficient to withdraw smoke and gas from the fire source into the ducts and through the fans to a discharge away from the building. The withdrawal of building air creates a partial vacuum near the fire source which is lower than atmospheric pressure and lower than any other air pressure in the building. Fresh, uncontaminated replacement air enters the building through intakes on the outside perimeter of the building and follows the pressure gradient created toward the fire source.