Overview of North America explosion-proof certification system

1.North America NEC explosion-proof authentication system

1) Two systems of NEC series standards

One is NEC500 series standard for divided native North American Division,specific use place involves the standard specification:

Article 500--Locations divided by hazardous classification;Article 501--Class I locations;

Article 502--Class II locations;

Article 503--Class III locations;

Article 504--Intrinsic safety system;

Another is NEC505 series standard divided by Zones in IEC series; specific use place involves the standard specification:

Article 505--Locations in Zone 0,Zone 1,Zone 2.

Article 506--Locations for combustible dust or fiber/flyings in Zone 20,Zone 21,Zone 22.


2) NEC500 series standard is the standard in local North America,it has comparatively large difference in regulations and requirements with IEC series standard,the countries and regions are mainly the United States and Canada and surrounding areas.References in the field of explosion-proof for NEC standard,main certification are NEMA,UL,CSA explosion protection,etc.


3) NEC505 series standards based on IEC standard,basic equivalent to IEC standards.Such as product finally use in the United States,Canada and surrounded countries and regions,the product takes NEC standards,whether NEC500 or NEC505 can be recognized,but because of the same standard of NEC505 and IEC,so,if products have been approved by IEC certification,in accordance with the corresponding NEC505 standards for testing and evaluation,it is very easy to meet the requirements.


4) Whether products are NEC500 or NEC505 can be recognized by America,Canada and surrounding countries.


2.Common sense of authentication for explosion-proof products of North America NEC505 and NEC500

1) American UL and Canadian CSA certification bodies,explosion-proof product certification executes NEC500 and NEC505 two modes of directives,NEC500 directive requires complete execution of the technical standard of United States or Canada federal.NEC505 directive follows IEC60079 technical standards.


2) Whether executes NEC500 instructions or NEC505 for product certification,it needs the inspection of factory,focused on certificated products,the review frequency is 4 times a year,may be 6 times a year and even more if there are many product specifications.


3.Certificates issued by United States UL and Canadian CSA three certification authorities

UL certificate is the most influential,then CSA certificate.From customer feedback information of current business process,basically need UL certificate.Three certification bodies do not accept test data and reports of others,this is the biggest difference between international IECEx and European ATEX certification system.IECEx,ATEX system stipulate that as long as it is the member of authentication institutions within the organization,regardless of which test data or reports issued by certification bodies,other members of the organization must accept.