The latest Titanium Purge Monitor from HFT (Huntingdon Fusion Techniques Ltd) incorporates a universal cut-off feature for interlocking with automatic or manual TIG/GTAW welding equipment. The feature allows welding to be stopped when oxygen levels reach preset concentrations so that welds are protected from oxidisation, porosity and unwanted reactions, precluding the need for rewelding and avoiding weld failures and reducing the need for costly inspection procedures. The HFT Titanium Purge Monitor is believed to be the only monitor specifically manufactured for welding titanium and is calibrated at 10 parts per million (ppm), or 0.001% oxygen. Most oxygen or purge meters used in welding are calibrated at atmospheric levels (20.9%) and therefore unsuitable for titanium or stainless steel use. Most meters or monitors are slow to react at low oxygen concentrations and can take more than a minute to show a rise above presets, so that a weld can be fully completed and passed when it is actually contaminated or oxidised. The HFT Titanium Purge Monitor shows an accurate reading throughout the welding process, allowing monitoring in real time. The system interlock interfaces with most welding equipment to cut or suspend electrical supply to the tungsten electrode in the event of oxygen levels reaching or exceeding the variable preset. The instrument is suitable for use with all exotic metals as well as titanium and stainless steel.