A Descriptive Analysis of Prehospital Response to Hazardous Materials Events

Little is known about the overall frequency of hazardous materials (HazMat) events in the United States and the nature of prehospital care for those exposed. The purpose of the current study was to perform a descriptive analysis of Emergency Medical Services (EMS) activations reported to a national EMS database.

Analysis of the 2012 National EMS Information System (NEMSIS) Public Release Research Data Set v.2.2.1, containing EMS emergency response data submitted by 41 states, was conducted. Mandatory data elements E0207 (Type of Response Delay), E0208 (Type of Scene Delay), and E0209 (Type of Transport Delay) contained specific codes for HazMat events and were used to identify specific EMS activation records for subsequent analysis. Overlapping data elements were identified and combined in order to prevent duplicate entries. Descriptive analyses were generated from the NEMSIS Research Data Set.

A total of 17,479,328 EMS activations were reported, of which 2,527 unique activations involved HazMat response. Mass-casualty incident was coded for 5.6% of activations. The most common level of prehospital care present on scene was Basic Life Support (BLS; 51.1%); 2.1% required aggressive Advanced Life Support (ALS) response. The most common locations for HazMat activations were homes (36.2%), streets or highways (26.3%), and health care facilities (11.6%). The primary symptoms observed by EMS personnel were pain (29.6%), breathing problems (12.2%), and change in responsiveness (9.6%). Two percent of HazMat activations involved cardiac arrest, with 21.7% occurring after EMS arrival. Delays in patient care included response delay, scene delay, and transport delay.

Hazardous materials events are rare causes of EMS activation in the United States. The majority occur in non-industrial venues and involve two or fewer patients. Scene time frequently is delayed due to multiple barriers. Cardiac arrest is rare but occurred after EMS arrival in one-fifth of patients.