Testing and Standards for Pellets and Combustion Equipment

U. S RESIDENTIAL PELLET FUEL STANDARDS
"The Pellet Fuels Institute (PFI) has established national standards for residential pellet fuel. Fuel quality certification is the responsibility of the pellet manufacturer. 
Two fuel grades have been established: premium and standard. Four fuel characteristics are prescribed in the grades. The only difference between the two grades is in the inorganic ash content."

pelletheat.org/fuel/fuel.html?83327.shtml~main

Two grades of pellets are established by the standard, premium and standard, with the principal difference being maximum allowable ash content, 1% and 3%, respectively.  Prairie grass pellets will almost always exceed the 3% limit, and the standards will need to be modified or another grade established to accommodate their use. 

FUEL CERTIFICATION AND TESTING
"The pellet fuel industry, through its trade association, Pellet Fuels Institute (PFI), has determined that it shall be the individual fuel producer's responsibility to test and certify each product. 
It is recommended that the manufacturers conduct both in-plant and independent laboratory tests of pellet fuel on a regular basis. Independent testing labs operate in most parts of the U.S. and Canada. 
Testing labs perform standardized tests according to ASTM procedures."

pelletheat.org/fuel/fuel.html?83327.shtml~main

SP Swedish National Testing and Research Institute

Certification of pellet burners and pellet boilers by P-marking

Abstract

"A product can be granted permission to display the P-symbol after certification by SP. Such certification involves verification that the product fulfills applicable requirements in respect of standards, codes of practice for the sector concerned, regulations, etc., and that there is verified and approved continuous inspection of the product. These certification rules describe the conditions for certification, technical requirements, and requirements for continuous inspection of pellet burners and pellet boilers. The technical requirements include characteristics to guarantee minimum levels of safety, efficiency, and reliability, as well as maximum emission levels. Continuous quality control is performed mainly by the supplier and consists among others of final inspection of completed products. Surveillance inspection is performed by SP with the purpose of ensuring that the supplier’s inspection procedures are operating properly. During these inspections, samples of completed products can be taken for subsequent performance testing."

Keywords: pellet burner, pellet boiler, P-marking, requirements, quality control, certification.