Faculty and Researcher Directory

Jack Dennerlein

Adjunct Professor of Ergonomics and Safety

Department of Environmental Health

Building 1, 1402
665 Huntington Avenue
Boston, Massachusetts 02115
Phone: 617.373.5428
jax@hsph.harvard.edu

Professor, Northeastern University, Bouvé College of Health Sciences, Department of Physical Therapy, Movement and Rehabilitation Sciences

Co-director, Occupational Injury Prevention Research Training Program

Director, Occupational Biomechanics and Ergonomics Laboratory:
Our research aims to prevent work-related musculoskeletal disorders (MSDs) through understanding the injury mechanisms based on hypothesis-driven laboratory and field studies using biomechanics, neuromuscular, exposure-response and intervention protocols and models.

Co-principal investigator, Harvard T.H. Chan School of Public Health,  Center for Work, Health, and Wellbeing, a NIOSH Total Worker Health of Excellence.

Research Interest

My research interest is in identifying pathways that influence and improve worker safety and health. Based in the field of modern ergonomics, our innovative research approach utilizes a systems framework that is driven by design of tools and organizations (programs and practices) with the goal of improving human well-being and system performance.

Identifying organization pathways that influence worker safety and health outcomes: At the heart of our work, especially our work at the Harvard T.H. Chan School of Public Health’s Center for Work, Health, and Wellbeing, we believe that workers and their health and safety behaviors are a response to the work environment.  Through organizational pathways, we can identify potential work organizational and work environmental factors that affect workers’ health.  We have documented relationships between health outcomes and an organization’s policies and programs. In patient care units, we have reported associations between worker low back pain and a unit’s ergonomic practices.  In construction we have documented associations between an organizations safety climate and worker injury outcomes.  From these observed associations and theorized pathways we have built a conceptual framework routed with a systems approach that serves as a road map for our research within the Center.

Intervention evaluation (comparative effectiveness) studies of workplaces programs and tools aimed at improving worker safety and health (Construction, Health Care, and Trucking) Our intervention research spans several industries as well as spanning both organizational and physical ergonomic interventions.  In terms of organizational ergonomics, we have developed and tested workplace programs on construction worksites.  Our Bulding Safety for Everyone project tested through a cluster randomized controlled trial, demonstrated a significant and improved effect on worksite safety climate scores through a low cost safety communication and recognition program that emphasizes safe working conditions rather than reports of injuries.  Our All the Right Moves project (ARM) is currently examining the effect of a Total Worker Health program that integrates an ergonomics program into existing safety practices with a wellness week custom designed for construction workers.  In terms of physical ergonomics, our Ride Project is testing the effects of a new tool, a seat suspension system that reduces whole by vibration by 50%, has on reducing trucker driver low back pain and fatigue.  Our pilot studies that demonstrated a 25% reduction in low back pain scores with the use of this vibration –canceling technology.

Exposure assessment of physical risk factors and musculoskeletal disorders (Office, Trucking, and Mining): While in theory physical risk factors are thought to WBV in Miningbe the immediate cause of work-related musculoskeletal disorders the empirical evidence linking these factors to outcomes has been limited due to the difficulty associated with directly measuring these risk factors. We have developed methods utilizing state of the art technology to measure risk factors for office workers and vehicle operators ranging from taxi drivers to heavy equipment operators in open pit coal mines.   Through these methods, we have documented relationships between duration of computer use and acute reports of upper extremity pain as well as identified physiological pathways for stress to enter the body.  Specifically, we have measured increased shoulder muscle activity in a set of office workers reporting higher job stress. We also documented that these stressed workers take fewer breaks than their less stressed counterparts.  For taxi drivers and operators of heavy equipment operators we have developed estimates of whole body vibration exposure based on driving records and vehicle characteristics.  For both we have observed associations between the health outcome and the exposure as well as high risk exposures.

The effects of computer technology and tool design on upper extremity biomechanics:  Within the ecological framework of computer related musculoskeletal disorders, computer technology has a direct effect on the biomechanics of the user.  As a result, this technology places loads on the upper extremity, increasing risk for these disorders.  However, as technology changes to include more mobile computing technology and dynamic workstations such as sit-to-stand desks the effects of these jennyComputerPROOFchanges are often unknown.  Our work has continuously followed technology and evaluated the effects of design on the proximal outcomes of biomechanics.  We have demonstrated that devices do matter and that some, but not all innovative designs can reduce biomechanical load.  Our results have both influenced and validated the design of devices that are currently on the market. In addition, we have developed user and designer guidelines to optimize upper extremity biomechanical loads.

Affiliations within Environmental Health

Education

Ph.D., 1996, UC Berkeley
S.M., 1989, MIT
B.S., 1986, University at Buffalo

In the Press

New York Times Magazine  Kennedy P (2012) Who Made That Escape Key?  5 October 2012

Cook’s Illustrated  (2013) Chef’s Knives.  September 2013

Boston Magazine   (2016) Six Tips for Using Standing Desks Correctly 10 May 2016

Reuters  (2016) Safe patient handling linked to fewer worker injuries. 4 November 2016

Selected Publications

Eijckelhof BH, Huysmans MA, Blatter BM, Leider PC, Johnson PW, van Dieën JH, Dennerlein JT, van der Beek AJ. Office workers’ computer use patterns are associated with workplace stressors. Appl Ergon. 2014 Nov;45(6):1660-7.

Sparer EH, Herrick RH, Catalano P, Dennerlein JT. Safety Climate Improved through a Safety Communication and Recognition Program for Construction: A Mixed Methods Study.  Scandinavian Journal of Work, Environment, and Health. 2016 Jul 1;42(4):329-37

Dennerlein JT, O’Day ET, Mulloy DF, Somerville J, Stoddard AM, Kenwood C, Teeple E, Boden LI, Sorensen G, Hashimoto D.  Lifting and exertion injuries decrease after implementation of an integrated hospital-wide safe patient handling and mobilization program. Occup Environ Med. 2016 Oct 25. pii: oemed-2015-103507. doi: 10.1136/oemed-2015-103507. [Epub ahead of print]PMID: 27919058