What is in this article?:
- How to tilt test a fire apparatus
- NFPA's standard response
The NFPA 1901 committee recommended an addition to the standard that would provide for three methods of addressing the problem of rollovers. Learn about their pros and cons and the flexibility provided by them.
(Article appeared in print as "Degrees of certainty")
Getting to the scene of an emergency is of paramount importance. And it must be done safely under a variety of weather, traffic and road conditions. After all, it is an emergency response and the public doesn’t always respond well to emergency vehicles.
National Fire Protection Association statistics show that, over the years, a significant proportion of firefighter injuries and deaths occur responding to or returning from an emergency scene. These statistics cover various types of fire apparatus, as well as POVs (personally operated vehicles), which involve both single- and multiple-vehicle incidents. Certainly there are numerous causes of these incidents, but regardless of what driver is in the wrong or what happened the physics of the incident are usually pretty straightforward.
Identifying the rollover problem
A notable proportion of fire-apparatus incidents involved vehicle rollover with property damage, as well as personnel injury and deaths. In addition to the monetary and human loss in such incidents, it was obvious the fire apparatus didn’t get to the fire, thus indirectly causing even greater losses. And the loss of an apparatus, which could not be replaced overnight, reduced the ability of a fire department to provide fire protection in their response area. Over a 10-year period, statistics gathered have shown an overall reduction of firefighter deaths and injuries in vehicle-related accidents, with some 16% of deaths and injuries in 2011occurring responding to or returning from alarms. Additional incidents occurred with minor injuries and property damage. There were some spectacular rollover incidents were included in the data. Whether a single-vehicle incident or one initiated by a collision, a rollover is a serious event to both personnel and apparatus.
A review of such rollover incidents indicated there were several causes: driver error, road conditions, weather, improper vehicle weight distribution, and high vertical centers of gravity. While there were several automotive industry standards relating to vertical center of gravity (VCG) values, including the Society of Automotive Engineers’ SAE J2180 and various National Highway Transportation Safety Administration (NHTSA) standards, there was no fire-apparatus industry standard. NFPA 1901, Automotive Fire Apparatus, long has addressed vehicle weight and balance as it relates to axle loading, as well as lateral and longitudinal centers of gravity. Based on the dismal incident record of vehicle rollover, something had to be done to reduce the toll of rollover incidents.
NFPA is an authoritative source on various public safety subjects and develops, publishes, and disseminates more than 300 consensus codes and standards. Several of the standards relate to motorized fire apparatus and (while voluntarily adopted by an authority having jurisdiction) are the de-facto standard for the industry. The most important standard pertaining to apparatus design and performance is NFPA 1901. There are additional standards that pertain to various types of fire apparatus and operations:
- NFPA 1002, Fire Apparatus Driver/Operator Professional Qualifications
- NFPA 1451, Fire Service Vehicle Operations Training Program
- NFPA 1911, Inspection, Testing, Maintenance and Retirement of In-Service Automotive Fire Apparatus
Each NFPA standard is generated and monitored by a voluntary committee composed of apparatus manufacturers, fire-department representatives, insurance company representatives, special experts and regulatory agent who update the contents on a general four-year cycle, although amendments and changes may be submitted at any time for review by the committee. The makeup, activities, and administration of these standards and its updating are well defined and documented by the NFPA.
After considerable discussion, research, documentation, testing, calculations, conversations, and discussions the NFPA 1901committee recommended an addition to the standard that would provide for three methods of addressing the problem of rollover. Each of the three solutions has pros and cons, but provides flexibility for small to large manufacturers, using custom or commercial chassis for various apparatus configurations, to meet the standards. It was recognized that almost every unit is custom-designed and -equipped.