Liquid Oxygen

The objective of this research was to verify and qualify what has been traditionally taught as fact during first responder’s hazardous materials training regarding response precautions to and the likely behaviors of liquid oxygen (LOx) during a release. Subject matter experts disagreed that these precautions were well-founded in precedent or science. Findings showed that impact pressure causes a reaction in LOx and asphalt under specific conditions. These conditions are not realistic during an emergency response. No reactions were observed by combining LOx with common saturated and unsaturated hydrocarbons and alcohols. No reactions were observed driving fire apparatus through a LOx pool on asphalt. No reactions were observed by combining LOx and combustible materials. No reactions were observed when spark ignition was used as a source for combustion. Pilot ignition sources were introduced directly into a LOx pool on asphalt without a significant reaction. Immediate and violent reactions were observed when pilot ignition or arc ignition was used to initiate combustion when combustible materials were in an ultra-high gaseous or liquid oxygen environment. Without flaming or arc ignition sources, no reactions were observed.

Traditional LOx Response Precautions Tested in this Study:

Do not step on the frozen asphalt because it may explode
Do not drive over the frozen asphalt because the weight of the vehicle could cause a detonation
Do not allow LOx to contact combustible materials, such as dried grass in the median or hydrocarbons such as diesel fuel, because it will ignite spontaneously resulting in a fast and intense fire
Always wait 30 minutes after the last frost is gone before stepping on the asphalt due to a potential explosive reaction.

The Liquid Oxygen Program
Utah Valley University
Emergency Services
Email: LiquidOxygen@uvu.edu

Liquid Oxygen Photos