n America, although safety certification is not compulsory. In fact, if the product doesn’t have a safety mark on it, it’s hard to access the market. Retailers and distributors want to sell products with the safety mark which recognized by the public. When consumers buy the products, they also always first to see if there is a safety mark on the products.

UL, ETL, MET, CSA labs are National Recognized Test labs recognized by OSHA. They all can perform the test on the products, and issue the certificates after the tests pass.

Application requirements

Any electric, mechanical and electrical product with safety logo on behalf of the manufacturer accepting regular factory inspection to ensure quality consistency, implies that this product comply with relevant requirements of USA and Canada safety certification. 
<img title="" alt="" data-cke-saved-src="data:image/png height=" src="data:image/png height=" 299"="" width="650" style="border: none; color: rgb(102, 102, 102); font-family: 'PT Sans', arial; font-size: 17.9104px; line-height: 24px; text-align: justify;">

Certification bodies	UL	ETL	MET	CSA
Mark
Nature	Voluntary	Voluntary	Voluntary	Voluntary
Initial Factory Inspection	Yes	Yes	Yes	Yes
Quarterly Factory Inspection	Yes	Yes	Yes	Yes
annual fee	Yes	Yes	Yes	Yes
The certificate is valid	Factory inspection normal, normal pay an annual fee, then remain in effect, if the new flag out, to do the standard update