Sample HyRAM output: plots of jet flame temperature and heat flux for user-defined hydrogen releases; PLL, FAR, AIR, and frequency of unignited releases from a user-defined hydrogen installation.
Risk Metric Value
PLL 7.362 x 10-5
FAR 0.0168
AIR 3.362x10-7
Scenario End State Type Avg. Events/Year
100pct Release No Ignition 0.0008
10pct Release No Ignition 0.0012
1pct Release No Ignition 0.0015
0.1pct Release No Ignition 0.0050
0.01pct Release No Ignition 0.0348


Developing hydrogen codes and standards is challenging because the relevant models and information span multiple science and engineering disciplines. The HyRAM toolkit integrates state-of-the-art models and data for assessing hydrogen safety. HyRAM provides a common platform for stakeholders conducting quantitative risk assessment and consequence analysis for hydrogen systems. The resulting information provides the scientific basis to ensure code requirements are consistent, logical, and defensible.

Katrina M. Groth, Ethan S. Hecht & John T. Reynolds. Methodology for assessing the safety of Hydrogen Systems: HyRAM 1.0 technical reference manual. SAND2015-10216, Sandia National Laboratories, Albuquerque, NM, November 2015. 


HyRAM 1.0 User guide. Katrina M. Groth, Hannah R. Zumwalt & Andrew J. Clark. HyRAM V1.0 User Guide. SAND2016-3385 R, Sandia National Laboratories, Albuquerque, NM, March 2016. 

HyRAM overview webinar and slides:



  • H2 HyRAM forums.