Tractor Rollover Protective Structures Research Articles

ROPS commentary-Addressing our fatal blind spot: Applying evidence-based solutions to reduce the most frequent cause of death on U.S. farms.

Tractor overturns are the most prominent contributing factor to death on U.S. farms and have been for decades. While public health researchers hypothesized years ago that overturn fatalities would largely disappear as older tractors were replaced by newer ones, this has not happened. In the meantime, farmers continue to die in these easily preventable and tragic events. Not only are tractor rollover protective structures (ROPS) 99% effective in preventing death in the event of an overturn, a national program exists to connect farmers with ROPS. While this program has been popular with farmers, and the cost-effectiveness of providing farmers with technical support and cost-sharing rebates has been demonstrated, many states lack access to ROPS rebates, even those states with the highest number of overturn fatalities. Given the evidence, it is difficult to reconcile the lack of policy or public investment in a solution that decisively addresses the most pernicious contributor to death in the agricultural industry. In this commentary, we highlight the science behind this proven solution to tractor overturns and the essential role that the media and implementation science can play in encouraging policy-makers to save lives.

Correction to: Determination of the Properties of the Rubber Mounted under the Agricultural Tractor Rollover Protective Structure Cabin Using a Hyperelastic Tensile Test and Finite Element Analysis

Due to an unfortunate oversight the acknowledgement section has been omitted.

Determination of the Properties of the Rubber Mounted Under the Agricultural Tractor Rollover Protective Structure Cabin Using a Hyperelastic Tensile Test and Finite Element Analysis

This study was carried out to determine the properties of materials used in the rubber mounted under the agricultural tractor rollover protective structure cabin. The natural rubber specimens were subjected to a hyperelastic uniaxial, biaxial, and planar tensile test, and a volumetric compression test for each of the four shore hardness types. The validity of the properties was assessed using ABAQUS, a commercial finite element analysis program. As a result of measuring the stress-strain curve with five repetitions of loading-unloading within each strain range, it was observed in all test results that the stress gradually eased from the initial level as the number of load iterations and strain intervals increased. The nominal tensile stress was shown in the order of uniaxial, planar, and biaxial tensile test. The nonlinear material models were similar to the tensile test results, and the Ogden 3rd model showed the best performance.

Operator protection in rollover events of articulated narrow track tractors

Articulated steering arrangements, wheeled or tracked, are commonly used on agricultural tractors and earth moving machines. In Continental Europe and Italy in particular, this configuration is typical of narrow track tractors. Despite their widespread use, there is little research that specifically investigates articulated tractor rollover protective structure (ROPS) in-field performance with respect to the ROPS test procedures. The aim was to investigate the relevance of the standardised ROPS test procedures regarding articulation joint mobility. The shortcomings of the procedures concerning the Clearance Zone and ROPS testing are evidenced and discussed. It is a recommendation of this work that an update of the international testing procedure be developed for articulated tractor types. The paper indicates how this may be accomplished and presents remedial measures that can be implemented in the interim until this latter goal is achieved.

Tractor ROPS and Stability Research: Introduction to this Special Issue.

Agricultural production has clearly benefited from the development of the tractor. The tractor provides a traction device and mobile power source. However, operating large equipment with high clearance on uneven ground leads to stability and overturn issues. Around the world, tractor overturns are still a leading cause of agricultural production fatalities. This special issue of the Journal of Agricultural Safety and Health focuses on recent research on tractor ROPS (rollover protective structures) and stability. Engineers and scientists in both Italy and the U.S. have been working on these topics, attempting to solve old problems and address rising issues. Understanding the factors leading to tractor instability, investigating the structures protecting the operator, and examining the continuous roll potential will all lead to increased operator protection and reduced fatalities.

Anthropometric procedures for protective equipment sizing and design.

This article presented four anthropometric theories (univariate, bivariate/probability distribution, multivariate, and shape-based methods) for protective equipment design decisions. While the significance of anthropometric information for product design is well recognized, designers continue to face challenges in selecting efficient anthropometric data processing methods and translating the acquired information into effective product designs. For this study, 100 farm tractor operators, 3,718 respirator users, 951 firefighters, and 816 civilian workers participated in four studies on the design of tractor roll-over protective structures (ROPS), respirator test panels, fire truck cabs, and fall-arrest harnesses, respectively. Their anthropometry and participant-equipment interfaces were evaluated. Study I showed a need to extend the 90-cm vertical clearance for tractor ROPS in the current industrial standards to 98.3 to 101.3 cm. Study 2 indicated that current respirator test panel would have excluded 10% of the male firefighter population; a systematic adjustment to the boundaries of test panel cells was suggested. Study 3 provided 24 principal component analysis-based firefighter body models to facilitate fire truck cab design. Study 4 developed an improved gender-based fall-arrest harness sizing scheme to supplant the current unisex system. This article presented four anthropometric approaches and a six-step design paradigm for ROPS, respirator test panel, fire truck cab, and fall-arrest harness applications, which demonstrated anthropometric theories and practices for defining protective equipment fit and sizing schemes. The study provided a basis for equipment designers, standards writers, and industry manufacturers to advance anthropometric applications for product design and improve product efficacy.

Editorial--Retrofitting Roll Bars and Seatbelts for Old U.S. Tractors to Prevent Farm Deaths: Now or Never

[first paragraph] In the United States, farm worker deaths from tractor rollovers represent failures in prevention, in that we have all of the knowledge needed and a viable intervention has long existed. In 1985, U.S. tractor manufacturers widely agreed to implement a new ASAE (now ASABE) standard (ASAE, 1985) for tractor rollover protective structures (which this editorial will refer to as roll bars) to apply henceforth to virtually all new tractors to be sold in the U.S. Unfortunately, there was no concomitant agreement or regulation applied to existing tractors, in use and/or when offered for resale. While the intention of having foregone retrofitting older tractors may have seemed, at the time, worthwhile to reduce cost burdens on lower-income farmers, the result has been tragic: a vexing persistence of tractor rollover deaths in the U.S. An average of over 100 farmers and farm workers per year (the majority of them middle-aged or elderly, often farming small-scale, marginal operations in counties with lower socioeconomic status) died this way from 1992 through 2005 (with many additional deaths among children using such equipment or riding along). This tragedy is doubly compelling because these deaths are almost entirely preventable by the use of a properly designed and installed roll bar and seatbelt.

An Australian experience with tractor rollover protective structure rebate programs: process, impact and outcome evaluation

The purpose of this study was to assess the effectiveness of the tractor rollover protective structure rebate program carried out by the Victorian Workcover Authority (Vic., Australia) in 1997–1998. The program was described using existing documents and records. Quantitative and qualitative information on tangible and intangible benefits were gathered through interviews with program applicants and other key informants. Information on the applicants and their tractors was obtained by analyzing the rebate application data. A cost-benefit analysis was conducted. The proportion of unprotected tractors was reduced from approximately 24%–7%. The program cost 7,886,067 Australian dollars ($AUD), which based on the projected prevention of 20 deaths over 10 years, equates to $AUD 290,668 per life saved. The lifetime cost per rollover death was estimated at $AUD 694,879 and $AUD 1,407,991 for the human capital and willingness to pay models, respectively. The success of the program is attributable to a range of factors, including legislative changes, publicity and awareness raising, and the financial incentive of the rebate. Benefits appear to outweigh any costs.