Prosecution Details

Being an employer, did not so far as is practicable provide and maintain a working environment in which the employees of the employer are not exposed to hazards and by that contravention caused serious harm to an employee, contrary to sections 19(1) and 19A(2) of the Occupational Safety and Health Act 1984.

Summary of Incident

On 18 May 2021, a worker (victim) was seriously harmed whilst using the Offender’s press brake machine (Press Brake) to “bump bend” a grade 2 titanium plate. 

The incident occurred at the Offender’s machining and heavy metal fabrication workshop business out of premises at Balcatta.

The victim suffered serious facial injuries as a result of the ejection of a projectile from the Press Brake.

The Press Brake

The Press Brake bends material by lowering a ‘punch’ or ‘blade’ tool into the sheet or plate material inserted below by the operator.  Fixed below the sheet of metal to be formed, in line with the punch, is a v-shaped ‘die’.  The punch and die come together when the punch is brought down to “bend the sheet”.  The action of the die hitting the metal is referred to as punching.

The die and the punch tools can be changed according to what is needed for the particular task.  The die is a tool with several fixed die sizes.  The operator can rotate the die to select the desired die size or replace the tool entirely with a custom sized die.

The Press Brake is operated by pressing on its pedal twice.  The first press of the pedal causes the punch to hit the metal sheet.  The second press of the pedal bends the metal sheet.  If metal being bent under high pressure breaks, the metal being bent may become a projectile.

One process for which the Press Brake is used is the bump-bending of metals.  “Bump-bending”, also referred to as “bump pressing”, involves making a series of small bends or “bumps” to the sheet of metal that incrementally form a bend in the metal to achieve the desired shape. 

The main difference between bump bending and standard “radius bends” is that bump bending involves punching the blade tool only a small distance into the die (thereby producing a small bend) rather than all the way into the die (which would create a 90 degree / right angle bend).

The selection of the correct tooling for the bend being undertaken, being a blade and die, is a matter that must be considered prior to beginning a task.  Whether there are any risks associated with the choice of die is also a matter that ought be considered prior to beginning the task.

Bump Bending Titanium

Titanium has certain unique characteristics that affect its ability to be formed.  For example, it generally has lower ductility (i.e. lower ability to be shaped without breaking) and greater spring-back during forming (i.e. higher propensity to return to original shape after being bent) at room temperature than steel.

However, titanium and its alloys have a wide spectrum of properties, and when correct parameters have been established, tolerances similar to stainless steel are possible.

Grade 2 titanium for example has excellent weldability, cold formability (i.e. ability to be shaped at room temperature) and fabricability.  It is a “workhorse” and “garden variety” grade of material for industrial service.

The Offender was aware of the above characteristics of titanium but did not have in place a process that required the operator to consider those characteristics as part of their assessment of how to safely complete a job.  Rather, the Offender’s workshop manager considered the characteristics of titanium and its impact on the job (if any) before allocating the job to the operator.

Events leading up the incident

The Offender did not commonly perform bump bending of titanium although it had done it on some previous occasions including an identical job in 2018 involving 12 mm grade 2 titanium (Previous Job).

In early 2021, the managing director of the Offender, accepted the job the subject of the incident. The job was to construct impeller hubs with grade 2 titanium of 12mm thickness.  The task required the titanium to be formed by bump bending it using the Press Brake.

The task was passed onto the Offender’s workshop manager for allocation to a staff member. The task was allocated to the victim.

The victim did not have extensive experience working with titanium although had bump bent 2-3mm thick titanium before.

The workshop manager advised the victim of the job requirements through a short-handwritten document which said that the two sheets of titanium were to be ‘bump pressed’ to an internal diameter of 220mm using the Press Brake.

The victim commenced working on the task in the days prior to the incident.  He achieved a number of bump bends in the other piece of titanium without issue.

No formal job hazard analysis or risk analysis were undertaken prior to the allocation of the job to the victim. 

When the Offender received the Previous Job, it identified it as the same job that it commonly performed except it involved grade 2 titanium.  The managing director and the workshop manager conducted research on grade 2 titanium by studying published materials about it on the internet.  Based on the materials they read, they formed the view that grade 2 titanium could be bump bent the same way as stainless steel (which the Offender, including the victim, has significant experience in).

They also practised bump bending on scrap pieces of titanium and it behaved the same way as what the workshop manager had experienced with stainless steel.

Based on the above things, and because the job involved the same considerations as the Previous Job, the managing director and the workshop manager decided the Offender did not need to take any further steps by way of job hazard analysis or risk assessment before the victim could safely start the job.

Incident

On 18 May 2021, at approximately 7:00am, the victim was completing a task on the Press Brake, bump pressing a 484mm x 245mm, 12mm thick plate of titanium.  When the punch tool impacted the titanium sheet it cut through the titanium sheet and a section of the titanium broke away hitting the victim in the face.

The victim spent three days in an induced coma. He suffered injuries including:

1.1.                    47 facial fractures;

1.2.                    Intraoral bleeding;

1.3.                    A large 15cm facial laceration;

1.4.                    torn bottom lip with 2cm missing; and

1.5.                    permanent damage to his eye.

Knowledge of the Hazard

At the time of the incident a safe work procedure for the Press Brake was kept in the office at the workplace. The safe work procedure listed “exposure to projectiles and sharp objects”.  However, the safe work procedure was only shown to workers when they were learning the machine and was not regularly consulted or reviewed.

The victim was an experienced fabricator and boilermaker who understood the risks of operating the Press Brake and their control measures.  However, it was not routine for him to work on titanium.  The experience of the victim was a matter that ought to have been within the knowledge of the Offender. 

It was reasonably practicable for the Offender to have ensured that its employees did not bump press titanium without completing a formal risk assessment or job hazard analysis to identify potential risks, and the work processes and equipment and tools to eliminate those risks. 

The Offender plead guilty and was convicted on 11 October 2024. Sentencing was heard on 28 November 2024 and the Magistrate issued a fine of $250,000 and ordered costs of $5993.20