Kia ora koutou, 

In this newsletter we’re covering: 

• an enforceable undertaking at Mercury
• an emerging trend of security and theft incidents 
• reminders for safety cases, inventory management, pressure equipment, and safety-critical elements.

If you have a question or any suggestions, please email HighHazardsNewsletter@worksafe.govt.nz

Please continue to share this newsletter with your colleagues, including your company’s Health and Safety Representatives. 

Ngā mihi nui,

Nick Dawtry, Liam Gannon and Geoff Taylor – Deputy Chief Inspectors 

For those major hazard facilities (MHF) that have invested in risk reduction controls to meet their obligations under MHF regulations, you should expect others in the industry that have hazardous substances meeting MHF threshold levels to do the same. When the Government initiated a taskforce to look at workplace health and safety (read the report here), they specifically highlighted the need “to motivate compliance and create a level playing field, the new agency and the other regulators need to make better use of their existing enforcement tools.”   

Following a recent reorganisation within WorkSafe, the High Hazard team now includes hazardous substance specialists who will be visiting operators that are close to MHF thresholds as well as sites transiting substances that would normally meet MHF thresholds. When inspectors find operations that are over MHF thresholds, or storing product longer than specified in regulation, and have not notified WorkSafe that they are an MHF, enforcement action will follow. 

If you are not sure whether you are an MHF, contact WorkSafe. It’s better to be proactive and check, than be the subject of enforcement. You can also check using the calculator tool below.   

Ngā mihi,  

Dave Bellett

We have accepted an Enforceable Undertaking from Mercury NZ Limited (Mercury).  

An Enforceable Undertaking is generally used as an alternative to prosecution. 

During 2021 commissioning activities at Rotokawa Power Station, fluids with significantly different temperatures unintentionally mixed, resulting in a severe steam hammer event that damaged valves and pipework, leading to the loss of steam containment.  

Fortunately, no injuries were sustained in this incident, however PCBUs have a duty, so far as is reasonably practicable, to ensure that items of plant are installed without risks to the health and safety of persons at, or in, the vicinity of the workplace. 

There have been recent incidents of security breaches and theft within major hazard facilities. Bulk storage facilities near Wellington have been targeted. It appears that youths have entered the facility to steal sirens.  

We consider this a high potential incident due to risks to hazardous area controls through unknown devices brought onto the facility, as well as the potential for intruders to cause further damage.

Please ensure you have reasonably practicable security controls to prevent or limit the potential harm that could occur. 

There are examples of international major incidents caused by intruders.  

We expect that safety assessments and consequence modelling are revisited ahead of safety case revisions. 

Even if your substances and conditions have not changed, knowledge about safety assessments or consequence modelling may have changed since your last safety case. For example, vapour cloud explosions occurring without confinement.  

There may be new guidance published since the previous safety case submission, for example the Atkinson and Briggs assessment method in the 2019 IChemE Hazards 29 Paper 05 for Assessment of Toxic Risks from Warehouse Fires. 

We’d also like upper tier operators who are currently revising safety cases to review the safety case assessment report you were provided with when your current safety case was accepted. Clauses that were accepted with ‘future inspection topics’ point to areas that were not adequately covered in that safety case. 

Our quick guide summarises when and how to revise a safety case, and what we are looking for in revised safety cases.

We recently became aware of an operator who had been managing stock levels to stay below the upper tier threshold since they had been designated as a lower tier MHF in 2017.  

Changes had been made to their stock management systems and errors were introduced, which meant that in the peak of their season they could have been operating above the upper tier threshold for quantities of specified hazardous substances.  

The error revealed a misunderstanding of how the quantities of specified hazardous substances aggregate together, and that one substance may have more than one hazard category. This is critical information for any facility managing inventory levels to stay below an MHF threshold.  

Operators who are managing inventory levels to stay below a threshold should review their system for managing those inventories regularly and ensure the rules are understood. A comparison against the original notification to WorkSafe would be a good check to do.  

We have guidance on our website to help you calculate the maximum quanitites of specified hazardous substances.

WorkSafe inspectors have found that some operators are not complying with pressure equipment, cranes and passenger ropeways (PECPR) regulations.   

Operators are reminded if they have pressure equipment (including pipework) they will need to have a “current certificate of inspection” for the equipment from a certified inspection body.   

Inspectors may ask for these certificates at upcoming inspections. 

A safety-critical element is any part of a facility or its plant (including a computer program) that: 

(a) has the purpose of preventing, or limiting the effect of, a major incident;

(b) the failure of which could cause or contribute substantially to a major incident 

For major hazard facilities, both statements need to be true. For petroleum, either statement needs to be true

A reminder – don’t add anything to the definition of a safety-critical element (SCE) or you may end up discounting controls that should be SCEs. 

There are no criteria in the regulations about whether the control:

• is automatic or not 
• can be ‘easily’ tested or have its performance monitored 
• is currently effective or reliable.

For more information see the major hazard facilities, petroleum or geothermal areas of our website or contact us on HighHazardsNewsletter@worksafe.govt.nz