10  266CRH / 266CRT, 266CSH / 266CST MULTIVARIABLE PRESSURE TRANSMITTER  |  OI/266CXX/MODBUS-EN REV. A   
   
… 2  Use in potentially explosive atmospheres 
 
Ex Explosion protection aspects (United States and Canada) 
 
According to Factory Mutual standards for the assurance of 
fundamental safety requirements in the United States of 
America. Ratings are with or without integrated digital display. 
• FM 3600: ಫApproval Standard for Electrical Equipment for use 
in Hazardous (Classified) Locations, General Requirementsಬ. 
• FM 3611: ಫApproval Standard for Non-Incendive Electrical 
Equipment for Use in Class I and II, Division 2 and Class III 
Division 1 and 2 Hazardous (Classified) Locationsಬ. 
• FM 3615: ಫApproval Standard for Explosion-proof Electrical 
Equipment General Requirementsಬ. 
• FM 3810: ಫApproval Standard for Electrical Equipment for 
Measurement, Control and Laboratory Useಬ. 
• NEMA 250: ಫEnclosures for Electrical Equipment (1000 Volts 
Maximum)ಬ. 
 
According to CSA standards for the assurance of fundamental 
safety requirements in Canada. Ratings are with or without 
integrated digital display. 
•  C22.2 No 142-M1987: ಫProcess Control Equipment Industrial 
Products. 
•  C22.2 No 213-M1987: ಫNon-incendive Electrical Equipment for 
Use in Class I, Division 2 Hazardous Locations Industrial 
Productsಬ. 
•  C22.2 No 30: ಫExplosion-Proof Enclosures for Use in Class I 
Hazardous Locations Industrial Productsಬ. 
•  C22.2 No 25: ಫEnclosures for Use in Class II Groups E, F and G 
Hazardous Locationsಬ. 
•  CSA-C22.2 No 94-M91: ‘Special Purpose Enclosures Industrial 
Productsಬ. 
•  ANSI/ISA 12.27.01: ‘Requirements for Process Sealing 
Between Electrical Systems and Flammable or Combustible 
measuring medium’. 
 
 
Type of protection: 
 Certification 
(Code ET) 
The 266 transmitters have FM certification for the following 
hazardous location protections: 
 
Code ET ratings 
Explosionproof (US)  Class I, Division 1, Groups ABCD,  
T5 for Ta = Æ50 °C to +85 °C 
Flame-proof (US)  Class I, Zone 1, AEx d, IIC,  
T4 for Ta = Æ50 °C to +85 °C 
Explosionproof (Canada):  Class I, Division 1, Groups BCD,  
T5 for Ta = Æ50 °C to +85 °C 
Flame-proof (Canada)  Class I, Zone 1, Ex d, IIC,  
T4 for Ta = Æ50 °C to +85 °C 
Dust Ignition Proof  
(US and Canada) 
Class II, III Division 1, Groups EFG,  
T5 for Ta = Æ50 °C to +85 °C 
FM Approvals Certificate  USA: 
FM16US0066X 
 Canada: 
FM16CA0036X