1. Henrich Triangle Safety and Fire Presentation

Presentation on Heinrich Triangle.

1. Henrich Revisited

2. W H Heinrich Herbert William Heinrich was one of the foremost pioneers in the field of accident prevention . Born in Bennington, U S in 1881, He began working as an apprentice in the machinist trade at age 16 . In 1918, he joined the U.S . Naval Reserve as a Lieutenant Junior Grade, and was discharged in 1919 with the rank of Senior Lieutenant . At the age of 32, he joined the Travelers Insurance Company at Hartford , he served until his retirement in 1956 at age 74 . Beginning in 1938 Heinrich conducted safety courses for students at New York University for more than 20 years ,. In 1942, he was appointed as chairman of the War Advisory Board, Safety Section, providing assistance to the U.S. Army safety effort . In 1956, he was appointed as chairman and president of the Uniform Boiler and Pressure Vessels Laws Society. Heinrich died in 1962

3. The work of H. W. Heinrich as expressed in the four editions ( 1931, 1941, 1950, 1959 ) of his book Industrial Accident Prevention: A Scientific Approach covered a period of nearly 30 years. From 1933 to 1999, the death rate dropped 90 %. Could workplace studies made in the 1920s be valid in relation to the workplace as it now exists ? Heinrich’s studies, were done in the 1920s, And the workplace has been impacted since then by mechanization, automation, more stringent safety standards, improved knowledge

4. Heinrich’s View Accident Causation Model – 88:10:2 88 percent of accidents are caused by unsafe acts of persons 10 percent of unsafe mechanical or physical conditions 2 percent of accidents are unpreventable Foundation of a Major injury – 300:29:1 (similar accidents) 300 will produce no injury 29 will produce a minor injury 1 will produce a major injury Domino Theory of accident causation : He proposed a “five-factor accident sequence

5. Heinrich’s Philosophy 1. Heinrich’s expressed belief that “psychology in accident prevention is a fundamental of great importance” 2. His premise that “psychology lies at root of sequence of accident causes” 3. His insistence that “a total of 88 percent of all industrial accidents are caused by the unsafe acts of persons” 4 . His oft-repeated statement that “man failure causes the most accidents” 5 . The emphasis given in his accident causation model, called the accident sequence , to the faults of persons and to ancestry and environment , which identified the traits of individuals as the principal causative elements.

6. Methodology Claimed to have reviewed an estimated 75,000 cases in total 12,000 from insurance records 63,000 from plant records There is no data available for review, outside of Heinrich’s writings

7. Heinrich’s Definitions Accident “An accident is an unplanned and uncontrolled event in which the action or reaction of an object, substance, person or radiation results in personal injury or the probability thereof . Major injury is any case that is reported to insurance carriers or to the state compensation commissioner. Minor injury is a scratch, bruise, or laceration such as is commonly termed as a first-aid case.”

8. 88-10-2 rule 88:10:2 ratios had the greatest impact on the practice of safety and have done the most harm . According to Heinrich, man failure is the problem, and psychology is an important element in correcting it. He considered cause singular !!! The insurance claims files and records of plant owner cannot provide reliable accident causal data. If accurate causal data are not represented in the resource base, the validity of the study has to be questioned, and the resource base for the Heinrich study is questionable The preventive efforts are directed at the worker rather than on the operating system Unfortunately , the use of the terms unsafe acts and unsafe conditions focuses attention on the worker or a condition and diverts attention from the root causal factors that are built into an operation . The practice of safety can be moved forward if safety practitioners discard the terms unsafe acts and unsafe conditions and replace them with terms such as causal factors or risk factors and concentrate on the sources of the causal factors, most of which are systemic .

9. 300:29:1 Ratio He originally stated that in a unit group of 330 accidents, 300 result in no injury, 29 result in minor injury , and 1 results in a major or lost time case L ack of documentation questions their validity. In each of the editions following the first edition, the premise to which the ratios apply changed, with no explanation. Fourth Edition : It is estimated that in a unit group of 330 accidents of the same kind and involving the same person, 300 result in no injuries, 29 result in minor injuries, and 1 in a major or lost-time injury In multiple versions of the publication, there are indicators that unsafe acts must occur multiple times before a major injury occurs. “keep in mind that a careless act occurs approximately 300 times BEFORE a serious injury occurs” – Heinrich – 1st edition 3 Keep in mind that an unsafe act occurs several hundred times BEFORE a serious injury results” – Heinrich – 3rd edition 4 Major and minor injury calculation

10. The practice

11. Move Beyond the Triangle Heinrich’s theories have been valuable. We have to recognize that the causes of the major injuries are not necessarily the same causes as the accidents. By focusing on the causes of minor accidents we may not eliminate major accidents. Reporting requirements and processes have only improved since Heinrich created his axioms. Modern reporting expectations will only continue to improve the accuracy of accident and injury statistics. As safety professionals, we should stop managing based on statics and treat each accident as a unique event with unique precipitating causes.