Low Pressure Gas Hazards : Safety screens and wire-mesh guards should be placed round evacuated glassware and safety goggles or a face shield must be worn against the possibility of implosion. This particularly applies when large desiccators or Buchner funnels are being evacuated. 'Take care when connecting thin walled glassware to a vacuum line or filter pump. The rule is, don't do so ' unless it is designed to withstand low pressures. Glassware should be examined for flaws before it is evacuated. If a crack occurred in a vessel which was partially evacuated, the effect of this enormous force compressing the weakened flask would cause it to implode (i.e. to explode inwards) propelling , fragments of broken glass in all directions.

 Figure: (a) Buchner funnel (b) Vacuum desiccator (c) 'Protective wire-mesh guard