Shock-tube studies at the National Institute of Standards and Technology (NIST) and the University of Illinois at Chicago (UIC) have been used to examine the decomposition of 1-pentyl radicals in argon between (833-1130) K and (100-5000) kPa. High pressure limiting values of the product branching ratios appear to be approached at the highest pressures studied. Results agree well with a 'best-fit' model previously developed [ 1] and are consistent with an energy transfer value = (675 +/- 100) cm(-1) at 1000 K. Published by Elsevier B.V.