American Sensor Technologies Inc. (AST) has announced its compliance to ANSI/ISA 12.27.01-2003 for their AST4600 Explosion-proof Pressure Transmitter. ANSI/ISA – 12.27.01-2003 “provides specific requirements for process sealing between electrical systems and flammable or combustible process fluids where a failure could allow the migration of process fluids directly into the electrical system. Examples of this type of seal include diaphragm seals, thermowells, and pump seals.” Tested by the Canadian Standards Association (CSA), all AST4600 pressure sensors will now be engraved with the Single Seal marking to indicate compliance. The housing will include the ambient (-40 to 85C) and process (-40 to 125C) temperature range information, along with the CSA 30 Class 1 Division 1 Explosion-proof (Groups A, B, C, D) approval marking. AST4600s also offer Krystal Bondä Technology, allowing pressure measurement through a solid piece of stainless steel (no welds, oil-filled cavities, or internal O-rings). The approval most notably effects equipment subjected to inspection by mechanical, electrical, and instrumentation inspectors in Canada. Effective 1 October 2007, sensors on new or repaired equipment must be marked as a “Single Seal” or “Dual Seal” device in order to continue operation.