Tingguang Ma

A thermal theory for flammability diagrams guiding purge and inertion of a flammable mixture

Recently, a thermal method was proposed to recheck the concept of flammability by manipulating the competition between heating and quenching. This method is further explored here to reconstruct flammability diagrams, explaining the contribution of each component toward flammability change for a mixture. Based on the assumption that a diluent will not change the flame temperature at the flammability limits, these isothermal processes lead to a conservative estimation of the flammable zone. Although rough near the inertion point, the theoretical flammability envelop has the potential to guide future purging and diluting operations. It will be a powerful tool for both educational purposes and practical utilities.

Application of incident command system in emergency response

The Incident Command System (ICS) is a standardized approach typically structured into five functional areas: command, operations, planning, logistics, and finance. The system allows for the integration of personnel, facilities, equipment, procedures, and communications within an organizational structure. It is a mature system and has been used by industries for a long time to aid in the proper mitigation of industrial incidents. The course named “Hazardous Materials Incident Management” is taught in the Department of Fire Protection & Safety at Oklahoma State University, which is designed to prepare students to manage hazardous materials emergencies through extensive hands‐on trainings. This article shows three design scenarios and how the ICS procedures are applied by student teams during the field trainings. Emergency response can be safely and effectively accomplished only when procedures are established and standardized through appropriate training. The discussion will help the academia and industry to well prepare/train the next generation of both public and private sector emergencyresponse personnel.

Using critical flame temperature for estimating lower flammable limits of a mixture

Based on the thermal balance between quenching and heating potentials of each component (fuel/oxygen/diluent), a method of computing flame temperature is proposed. This method can be used to find the critical flame temperature at lower flammable limits or estimate the lower flammable limits with an assumed critical flame temperature.

Flammable state and dilution requirement in the theoretical flammability diagram

A generic method is proposed to use the flammability diagram to determine the flammable state of a mixture and the dilution requirements. All graphs are derived from theory, without any empirical constants. This method is comprehensive and consistent with a same treatment for fuel(s)/oxidizer(s)/diluent(s). The theoretical LFL lines are generally lower than the experimental lines due to the assumption on constant flame temperature. So, the prediction is usually conservative, which is good for estimation purposes.