Prosecution Details

Being a principal who, in the course of trade or business, engaged a contractor to carry out work for the principal in relation to matters over which the principal had the capacity to exercise control, failed so far as is practicable to provide and maintain a working environment in which the contractor was not exposed to hazards, and by that contravention caused the death of a person, contrary to sections 19(1), 23D, and 19A(2) of the Occupational Safety and Health Act 1984 (WA).

Background

Workplace and Employment

The offender, Orbit Drilling Pty Ltd (Orbit Drilling), is an Australian company with company registration number 078 788 735 and is based in Western Australia. The company was established on 4 June 1997. The main function of the company at the time of the incident on 9 May 2018 was exploration drilling.  There was one sole owner and director (the director).

At the time of the incident, Orbit Drilling was using the Malcolm Campsite as a base for some of its regional drilling operations in the area. The Malcolm Campsite included sleeping quarters, bathrooms, a laundry, and a temporary workshop (‘the Malcolm Campsite’).

The Malcolm Campsite is situated approximately 9km’s East of Leonora, towards Laverton, on the right side of the Leonora-Laverton Road.

There was a verbal agreement in place between director and the pastoralist regarding Orbit Drilling’s use of the Malcolm Campsite. No payment was received by the pastoralist for its use.

At the time of the incident, Orbit Drilling had approximately five mobile drill rigs in use at various locations and had 21 drill rigs in total.  Orbit Drilling employed both direct employees and contractors to perform its work. Orbit Drilling had approximately 18 direct employees and three contractors or sub-contractors.

On 9 May 2018, a direct employee of Orbit Drilling was the only employee at Orbit Drilling who had the title of “Supervisor”(the supervisor), and was therefore tasked with being a supervisor across several different sites.

The victim was a contractor regularly engaged by Orbit Drilling, usually on a ‘three week on, one week off’ roster.

Work Practices at the Workplace

Drill Rig 9 was a Rotatory Air Blast (‘RAB’)/Air Core Drill rig used for mineral exploration drilling. The rig was owned by the director’s other company ‘Drill Gold Pty Ltd’, however it was exclusively used by Orbit Drilling to complete various RAB/Air Core drilling contracts. Drill Rig 9 was at the Malcolm Camp Temporary Workshop at the time of the incident, and was mounted on the rear of an Isuzu 4wd truck.

One of the tasks carried out by Orbit Drilling’s employees and contractors was to change the function of Drill Rig 9 from RAB (percussion drilling) to Air Core (non percussion drilling). On average, this task would be carried out by Orbit Drilling’s employees or contractors once every 3 to 6 months.

The task requires the sub directly below the Air Swivel to be loosened and removed, this sub is sometimes referred to as the “Head Tube Locking Sub”, “Adaptor/Drive Sub”, or the “Under-Hung sub” (“the Head Tube Locking Sub”).

The procedure the supervisor and the victim were following to complete the task at the time of the incident was a system that Orbit employees had been using in order to break out bound threads on Drill Rig 9 prior to the incident.  It was an accepted Orbit work practice.  There was no specific written Safe Work Procedure (‘SWP’) in place to guide employees or contractors in performing the task.

Sometimes, when completing the task, the threads on the drill string become bound, this includes the thread between the Head Tube Locking Sub and the Air Swivel. When this occurs the workers are required to crack or “break out” that bound thread, in order to loosen the Head Tube Locking Sub so that it can be removed from the Air Swivel.

This involves using a “Stillson”, which is a manual tool, otherwise known as a pipe wrench (‘Stillson’). The jaws of the Stillson are placed into the tool flats of the sub. The Stillson is then manually pushed by one of the employees. This rotates the drill string anti-clockwise so that the handle of the Stillson is resting against the mast.

The driller then goes to the control panel, which is on the left side of the drill rig mast when facing the front of Drill Rig 9.  The next step is to place the Hydraulic Breakout Wrench, also known as a ‘modified Stillson’ (‘Hydraulic Breakout Wrench’), onto the bottom part of the Air Swivel just above the joint between the Head Tube Locking Sub and the Air Swivel.

One person then usually operates the drill control panel to move the levers which engages the hydraulic power and rotation of the drill. The other person works as an off-sider to assist the driller and re-position the Stillson or Hydraulic Breakout Wrench if required.

The way Orbit Drilling’s employees were taught to perform this task was for the driller to go to the control panel and the off-sider to stand out of the way. This is to ensure all workers in the vicinity of the drill were “out of the line of fire”. The “line of fire” was considered to be the arc the Stillson, which was backed up to the mast would create if the drill was rotated under hydraulic load, or if that Stillson, or the Hydraulic Breakout Wrench, were to break whilst under hydraulic pressure.

When both people are in their respective positions, the driller applies hydraulic rotation to the drill string by operating the rotation lever on the control panel. The direction of rotation being applied to the drill string during the task is reverse (away from the driller at the control panel). This in turn applies pressure to the Stillson that is resting against the mast. This pressure is to hold the Stillson against the mast, which should prevent the Head Tube Locking sub from moving when trying to break the bound thread.

There are three positions that the rotation lever can be put in; these are ‘forward’ (by pushing lever down), ‘neutral’ (middle), and ‘reverse’ (by pushing lever up). The three positions have a detent to hold the lever in position. The Hydraulic Breakout Wrench is activated at the same time the drill string is rotated under hydraulic load, which should cause the thread to undo or ‘break’.

If the thread between the Air Swivel and sub fails to break, or it binds, the process is repeated. The off-sider will usually not move in and reposition both the Stillson and the Hydraulic Breakout Wrench, until given ‘the all clear’ by the driller.

Orbit Drilling had no written Safe Work Procedure (‘SWP’) in place prior to, or at the time of the incident on 9 May 2018, in relation to the task of changing the drill function from RAB to Air Core. There was also no SWP In place for the task of breaking out the Head Tube Locking Sub from the Air Swivel.

The Incident on 9 May 2018

On 9 May 2018 at approximately 4.00pm, the supervisory and the victim were performing maintenance work on Drill Rig 9. The supervisory was a Senior Driller and Supervisor at Orbit Drilling. He had control over the work activities being performed.

The supervisor and the victim were performing the task of changing the drill function from RAB to Air Core. This was required to be completed in preparation for an upcoming drilling contract.  The supervisor deemed the victim to be a more experienced driller than himself in performing this task.

Shortly before the incident, the supervisor and the victim had a discussion as to how they were going to perform the task. It was agreed that when carrying out the task they would either both be at the drill rig table or both be near the control panel. The reason for this was to avoid the ‘line of fire’ issues with the Stillson attached to the Head Tube Locking Sub swinging around and hitting one of them, or the jaw heads of the Stillson or the hydraulic breakout wrench, snapping off when under hydraulic pressure.

They did not complete or sign a written Job Hazard Analysis Form (‘JHA’), or any similar document, prior to undertaking the task. Orbit Drilling did not have a policy in place requiring employees or contractors to complete these forms for this particular task. Neither The supervisor nor the victim were wearing appropriate PPE, such as a safety helmet, or ear protection.

The supervisor went and located a new red-handled 48 inch Stillson (‘the 48” Stillson’) from the workshop. The reason for using this brand new 48” Stillson was because he thought there was less likely to be fatigue in the metal, and the teeth would grip better.

The victim changed the other yellow-handled modified Hydraulic Breakout Wrench on the drill rig to a larger size before undertaking the task, as he determined the original Hydraulic Breakout Wrench was too small.

The supervisor then placed the 48” Stillson into the tool flats of the Head Tube Locking Sub to hold the sub in place. He then manually rotated the 48” Stillson attached to the sub, so the handle of the 48” Stillsons were resting against the mast. Around the same time, the victim placed the Hydraulic Breakout Wrench onto the bottom of the Air Swivel.

Once both the 48” Stillson and the Hydraulic Breakout Wrench were in place, the supervisor went to the control panel and the victim stood behind the supervisor.

The supervisor then applied reverse hydraulic rotation, by using the rotation lever on the control panel. This applied hydraulic pressure to the handle of the 48” Stillson resting against the mast. The supervisor had thought this initial turn had loosened the sub enough to undo it, however the thread between the sub and the Air Swivel was still bound.

The supervisor then removed or “backed off” the hydraulic pressure from the 48” Stillson and went to reposition it, as well as the Hydraulic Breakout Wrench. The victim assisted the supervisor in this repositioning task. Once the 48” Stillson and the Hydraulic Breakout Wrench were repositioned, the supervisor and the victim moved back away from the mast, and out of the “line of fire”. The supervisor remembers the victim standing out of his line of sight, which he took to be out of the line of fire.

They tried to break the thread four times, and each time it bound again. The process was repeated; namely the victim would wait for the supervisor to approach the mast and both of them would then reposition the 48” Stillson and the Hydraulic Breakout Wrench. Once the 48” Stillson and the Hydraulic Breakout Wrench were repositioned, they would then go back to the control panel and the supervisor would again apply hydraulic rotation.

The supervisor engaged the rotation lever to try and break the thread a fifth time. He looked at the Head Tube Locking Sub and determined the thread was still bound. He applied reverse pressure to the 48” Stillson once again to try and loosen the sub.

The supervisor looked back at the control panel and then back at the Head Tube Locking Sub. As he did this, he inadvertently placed the rotation lever out of neutral towards the forward detent position. This caused the 48” Stillson to swing around under hydraulic pressure, away from the mast. At the same time, the victim stepped forwards towards the mast, to reposition the Hydraulic Breakout Wrench, and was struck to the side of the head by the swinging 48” Stillson that was still attached to the sub.

The victim immediately fell to the ground from this blow to the head. The supervisor ran over and provided assistance to the victim.

Causation of Death

Shortly after the incident on 9 May 2018, the victim was transferred by work colleagues to the Leonora Hospital. He was subsequently transferred to Royal Perth Hospital and placed into intensive care and then palliative care.

The victim had received severe injuries to the right side of his head, this included extensive fracturing to his skull and an associated brain injury. On 20 May 2018 he died as a result of these injuries. He was 48 years old.

Hazard

The hazard (“Hazard”) in the working environment was a person working in the vicinity of a Stillson (pipe wrench), which was attached to any part of a drill that was being rotated under hydraulic power, which may result in serious injury or death.

Orbit Drilling’s failure to provide and maintain a safe working environment caused the death of the victim.

Foreseeability – Use of Manual Stillsons under Hydraulic Load/Power

Prior to, and at the time of the incident, it was common knowledge within the industry that a Stillson (pipe wrench) is a manual tool only and it was not safe to use this tool under hydraulic power. Stillsons are only to be used for tasks that can be undertaken with the power of the drill string isolated. This is due to the fact they can break apart under hydraulic pressure, or swing around and strike someone in the vicinity of the drill rig, if the rotation lever of the drill rig is engaged.

In April 2002, the Department of Industry and Resources published a “Significant Incident Report No 113 – Driller’s Offsider being struck by Stillson type wrench”. The report included the following information:

      “INCIDENT: Recently an inipit RC grade control drillers offsider was struck in the chest by a “Stillson” type wrench, when rotation was released following torqueing up a joint. Over the past year two other accidents have been reported involving “Stillsons” being used to break out the thread of the drill rod components. A drill fitter on a blast hole rig received two broken legs when rotation was applied to the drill rod and in the other accident a driller sustained a serious injury to the abdomen

CAUSES:

• Rod break out procedures, detailing a safe work method, were not adequate.
• Poor communication between the drill crew contributed to each incident…
• Not using purpose designed tools to break out the rods.

COMMENT AND ACTION

• “Stillsons are a hand held tool designed with a long handle for (human) powered leverage only. “Stillsons” are not designed to facilitate hydraulic or machine driven motion.
• In all three cases persons were struck by “Stillsons” either under rotation or whilst releasing torque on a blast hole drill rig. It is the view of the Department that the use of “Stillsons” should be restricted to the limitations of their design function which is manual (hand) use only. “Stillsons” should never be used under hydraulic or machine power.

There were no Rapspan or Diaspan type spanners available on Drill Rig 9 at the time of the incident. These tools are designed for use under hydraulic power, and safely fall away if rotation is accidently engaged in the opposite direction. They were widely available for purchase on or before 9 May 2018, and were suitable industry tools for safely carrying out the task. Had Orbit Drilling purchased these tools and made them available to the supervisor and the victim, the incident would not have happened.

In November 2016, a client of Orbit Drilling had specifically requested that Orbit Drilling amend its risk assessment matrix to ban the use of ‘modified Stillsons’ (which was the yellow handled 36” Hydraulic Breakout Wrench to Drill Rig 9 at the time of the incident). The same matrix refers to the use of Rapspans to perform the task of breaking out threads. It follows, Orbit Drilling was aware, at least as early as 2016, that it was not appropriate to use manual Stillsons for breaking out threads, as Rapspan Spanners were appropriate.

At the time of the incident, it was also possible to have installed a hydraulic breakout unit to Drill Rig 9. This would have eliminated the need for direct human involvement when breaking out the thread between the Head Tube Locking Sub and Air Swivel. Again, if such a system had been installed, Orbit Drilling’s employees would not have been exposed to the hazard of Stillsons being incorrectly used under hydraulic load.

Orbit Drilling’s Conduct Following the Incident

On 10 May 2018, the day after the incident, Orbit Drilling ordered two Rapspan spanners at a cost of $5,500. Orbit Drilling ordered several more Rapspan and Diaspan spanners between 17 May 2018 and 9 August 2018.

On 17 May 2018, Orbit Drilling made enquiries with Hydco to receive a quote for fitting a hydraulic breakout unit to its air core rigs, such as DR09. Hydco confirmed this was possible at a cost of between $20,000 to $30,000.  Prior to the incident, Hydco had previously installed these safe hydraulic breakout systems on similar air core rigs for other clients.

On 18 May 2018, Orbit Drilling sent out an office wide email. The email reads as follows:

“ATTENTION ALL STAFF

There is to be NO use of Stillsons and pipe wrenches of any kind being backed up to the rig with hydraulic force applied.

Stillsons and Pipe Wrenches may be used on the rig but only manually and without the aid of “cheater bars”.

Please refer to the attached 3 page brochure for the correct use of pipe wrenches.

Only approved Wrapspanns can be used on the drill rig for breaking out rods, subs and hammers”.

Since 18 May 2018, Hydco have fitted two hydraulic breakout systems to Orbit Drill rigs. This include a hydraulic breakout system being installed on Drill Rig 6, in December 2018, at a cost of $62,030.75.

Orbit Drilling has also now developed a written SWP for Drill Rig 6 in relation to the safe use of a Hydraulic Breakout system on that rig when breaking threads on drill rods. The SWP is dated 18 February 2019. It includes a step by step procedure for operating the hydraulic breakout system to breakout threads on drill rods. It also outlines the minimum personal protective equipment to be used when performing the task, which includes an approved safety hard hat, safety gloves and ear protection.

The Offender plead guilty on 5 October 2021 and was then sentenced on 16 December 2021. The Magistrate put the nature of the offending at the higher end of the scale of seriousness. After taking into account aggravating and mitigating factors, the Magistrate arrived at a fine of $320,000 (and then applied a 20% discount for the plea of guilty). The total fine imposed was $256,000 (out of a maximum penalty of $400,000). Costs were ordered in the amount of $2,363.50.