DSS038: New Zealand Code of Practice For Handling Combustible Dusts With Dr. Chris Bloore

In this episode of the DustSafetyScience Podcast, we talk to Dr. Chris Bloore to talk about the New Zealand Code of Practice for handling combustible dust.

Chris has been a guest on the podcast before: in Episode #31, he talked about reconciling hygiene and explosion safety in food handling industries. He also went into brief detail about the New Zealand system for combustible dust safety and dust explosion safety, and today he’s back to go into further detail.

Chris is a Ph.D. and industry expert in spray drying applications. He spent 19 years with the New Zealand Dairy Research Institute and has been a self-employed consultant and educator in this space for almost 30 years. In this episode, he answers the following questions:

What are the regulations governing combustible dust safety and dust explosions in New Zealand?
What is their risk-based approach?
What obligations do employers have?
Is there a timeline for implementing changes?
What resources do injured workers have in New Zealand?

What Are The Regulations Governing Combustible Dust Safety and Dust Explosions in New Zealand?

Chris explained that New Zealand and Australia share joint standards on most safety engineering topics. With regards to combustible dust, the standards date back to 1998-99. At that time regulations were comparatively primitive, so a Standards Australia Working Committee got a subcommittee together and started developing a comprehensive combustible dust standard for Australia and New Zealand. Dr. Bloore served on that subcommittee for three or four years.

The standard was published as AS/NZS 4745 in 2004 and was updated slightly in 2012. It takes a comprehensive approach to dust explosion safety, covering things like:

Risk reduction
Hazard assessment
Safety requirements

According to Chris, there are also some comments on:

Plant design and factory operation
Plants that are handling, processing or creating dust
Emergency management

“It refers to both U.S. and European design standards so it’s not a design standard in itself,” he explained. “It’s basically an overarching document that spells out the appropriate ways of facing hazards and designing out out problems. It also covers the overall philosophy of safety using a risk management approach rather than a highly prescriptive approach.”

The subcommittee created Zones 20, 21, and 22 as dust classification areas for the purposes of designing electrical equipment so that ignition sources would not be placed in hazardous areas. It also covered ways of measuring the dust characteristics that might lead to a hazard, such as dust clouds and dust layers that might be subject to self-ignition under certain circumstances.

The philosophy of the standard was that if you identify a hazard, you need to take reasonable and practicable steps to mitigate it, avoid it or otherwise reduce the risk to operators and members of the public, etc.

“The objective is to have a safe workplace,” Chris said. “If you simply zone things, put electrical equipment in the areas where there’s no dust and keep them out of areas where there is, and then expect the factory to run safely, then you’re dreaming. So it’s part of the overall scheme. It’s an important part but it’s not the end of the game: it’s just the beginning.”

What Is The Risk-Based Approach?

One of the key features of the risk-based approach is that if a hazard is identified, you are given a reasonable period of time to sort it out. With serious hazards, you will be expected to cordon off the area and limit access. At all times, you are expected to take an active approach to combustible dust safety.

For example, if you assign a light zoning to an area for electrical purposes because there is so little dust, what happens if your workplace practices gradually degenerate to the point where there is a constant combustible dust cloud? There has to be an emphasis on the staff work practices and the constant presence of incentives and disincentives to do things safely.

“We (come across) incidents where there’s a lot of pressure and people (are)desperate to get the plant running again,” Chris warned. “They cut some corners, and the tragic thing is that most of the time they get away with it. And that then becomes the new normal. Then one day for no reason at all, things just go bang. So we’re looking at the entire process of designing, installing, operating, and maintaining the plant to achieve safety.”

What Obligations Do Employers Have?

In New Zealand, there is an obligation on the employer, which is a term used in a lot of countries. The person conducting a business or undertaking, or PCBU, is the legal entity that is responsible for the workplace. It might be a CEO, chairman of the board or, if it’s a small workplace, the manager of a small plant. They are legally obliged to maintain a safe workplace, which includes:

The various design features of the plant itself
Maintenance
Workplace practices

Referring to the latter, Chris said, “You might have a perfectly good JSA (job safety assessment) system, but what if the guy who was made to do the lockout-tagout hasn’t actually got the key to the padlock in his pocket? He does the work but somebody starts a fan up, he gets his fingers chopped off, and there’s a problem. So the work practices form a big part of the actual practical safety that is achieved underneath the standard. It does emphasize that how you do the job is quite important.”

Is There a Timeline For Implementing Changes?

When the New Zealand Dairy Code of Practice for spray drug safety came out in 1990, it had a clause stating that if a plant is going to be shut down and rendered obsolete within five years, you don’t have to make changes. If it’s going to be in use beyond five years, you have five years to comply, so by 1995, all of the plants were either dismantled or fitted with some form of explosion protection. There was an understanding that certain steps cannot be effectively taken overnight. However, this five-year window only applied during the implementation of the program. Now, any new plant has to comply with an approved code before it’ll be allowed to start.

AS/NZS 4745, which is the overarching combustible dust standard for New Zealand and Australia, requires you to use current design standards. You can use ATEX, VDI, or NFPA, or any other internationally recognized design standard that’s current at the time that the plant’s being designed.

“So you can’t (use) a 25-year-old standard because it’s cheaper,” Chris said. “The latest edition of each of these recognized standards shall be the one used. You can’t design a plant on a 20 or 30-year-old standard so that does tend to keep things up to date.”

What Resources Do Injured Workers Have in New Zealand?

In 1974, New Zealanders gave up their right to sue for personal injury in return for the establishment of the Accident Compensation Corporation (ACC), a government-run body that compensates people for personal injuries.

If someone is hurt in an industrial accident or struck by a motor vehicle, their compensation is paid from the ACC fund, which employers and employees pay into. It is a no-fault system, which means that the compensation is related only to the cost of medical treatment and loss of income regardless of whether it was an act of negligence or genuine accident.

Although the system prevents employers from being sued by an injured employee, they have still committed an offence regarding their general duty to maintain a safe workplace. If negligence or carelessness is involved, the company can still be prosecuted and fined, and due to strict liability, the director(s) can be fined individually or imprisoned. This system is a striking contrast to the situation in North America, which is highly litigious.

“One of the advantages of the system is that there is comprehensive record-keeping,” Chris added. “Anytime anybody gets injured and goes to the hospital or to a doctor or a physiotherapist or whatever, all of that is reimbursed by the ACC. So they’ve got absolutely 100% accurate records of what’s going on. We have excellent statistics (that aren’t) fudged by companies attempting to reclassify things or hide things under the carpet.”

“So, on the one hand, we’ve got this very good database,” he continued, “but on the other hand, we’ve got incentives for companies to be safe because there are penalties and liability and publicity. When the government publicly outs you for being unsafe, there’s nowhere to run. So it has actually worked very well.”

Conclusion

The DustSafetyScience tagline or mission statement for this year is understanding combustible dust as a global challenge and developing global solutions. It involves a critical examination of what safety laws and measures are in place in other parts of the world and seeing what works and what doesn’t.

We’ve spoken to Alan Tyldesley about the regulation environment in the United Kingdom; Michael Marrington about the IECEx System, and Arpad Varess about ATEX certification and qualified persons. On a similar note, Niklas Kitzhöfer has come on to talk about the regulation environment in China and Johannes Lottermann shared information about the VDI standards in Germany. Today, Chris Bloore discussed the New Zealand Code of Practice for handling combustible dust. The more information that is shared, the closer we come to developing the global solutions that will make a difference.

If you would like to discuss further, leave your thoughts in the comments section below. You can also reach Chris Bloore directly:
Email: [email protected]
LinkedIn: https://www.linkedin.com/in/chrisbloore/

If you have questions about the contents of this or any other podcast episode, you can go to our ‘Questions from the Community’ page and submit a text message or video recording. We will then bring someone on to answer these questions in a future episode