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NZ Hazardous-Substances Emergency Plan: Retest After a Change

September 29, 2026·15 min read

A workplace changes the person named to coordinate a hazardous-substances spill response. The written emergency response plan still lists the old coordinator. A replacement has been appointed and briefed, but no one has tested whether that person can perform the plan's role. The next annual exercise is months away. Does the business wait for it?

For a New Zealand workplace that is required to have a hazardous-substances emergency response plan under the relevant regulations, the answer may be no. Regulation 5.12 of the current Hazardous Substances Regulations requires the plan to be tested at least every 12 months. It separately requires a test within three months if a person, procedure or action specified in the plan changes. The test is meant to show that the new person can perform the role or that the new procedure or action works. A document update alone does not demonstrate that.

This guide explains the scope, trigger, practical test design, record and follow-up. It is a narrower companion to the live Complys New Zealand hazardous-substances overview, which introduces the wider rules. It does not decide whether a particular site's stock exceeds a threshold or design the emergency response for a specific substance. Those decisions require the actual inventory, classifications, quantities and workplace conditions.

First establish whether this plan rule applies

The three-month retest rule is not a general instruction for every office emergency plan. It sits in Subpart 2 of Part 5 of the Health and Safety at Work Hazardous Substances Regulations 2017. Regulation 5.6 links the subpart to specified hazard classifications, forms and aggregate quantities in Schedule 5. It also has special treatment for some petrol and related substances. Do not infer applicability from a single product name or copy a quantity from another workplace.

Start with a current inventory. Identify each substance's classification and form, the quantities present or likely to be present at the place, and the relevant Schedule 5 entry. Consider how the regulation aggregates quantities and any applicable special provision. WorkSafe's emergency-plan guidance points businesses to the hazardous-substances calculator as an aid in deciding whether an emergency response plan is required. A calculator output is a useful check, but the PCBU still needs correct inputs and an applicable legal basis.

If the subpart applies, Regulation 5.7 requires a PCBU with management or control of the workplace to ensure an emergency response plan is prepared. The plan covers reasonably foreseeable emergencies arising from failure of controls on hazardous substances present or likely to be present. Other emergency planning duties may also apply to a workplace. This article concerns the specific hazardous-substances plan and its test requirement, not every emergency-plan regime in New Zealand.

If the inventory has changed, first revisit whether the hazardous-substances subpart applies and whether the plan still reflects the hazards. A changed inventory entry is not, by itself, the exact three-month trigger in regulation 5.12. The trigger is a change to a person, procedure or action specified in the plan. A substance change may lead to such a plan change, or may require a wider reassessment of the plan and controls. Record what changed instead of treating every inventory update as the same legal event.

Read the two clocks separately

Regulation 5.12 has two timing rules. Subsection 1 requires a test at least every 12 months to demonstrate whether the plan is workable and effective. This is the regular test interval. Subsection 2 requires a test within three months when a plan-specified person, procedure or action changes. That is a change-triggered test. A business should be able to explain which rule prompted each exercise.

The three-month wording is an outer limit, not a suggestion to wait for three months when a new arrangement is plainly untested and a serious emergency could occur sooner. Scheduling an early test can make operational sense. Do not turn this editorial point into a claim that the regulation prescribes a shorter universal period. A PCBU should consider the risk and the functions changed when deciding how quickly to exercise the revised plan.

The annual test does not excuse a missed change-triggered test merely because it took place recently. If a plan names a new emergency coordinator after an annual exercise, the relevant question is whether the new person can perform the role. Conversely, a properly designed change-triggered test may also demonstrate that the plan works more broadly. The statute does not say that two entirely separate ceremonies must always be held. Record the scope and date of a test so it is clear which duties it satisfied.

Build an ordinary calendar around the date of the last valid test and a change log around the date a plan-specified person, procedure or action changed. A reminder can help, but the legal requirement is the completed test and record. If an incident, near miss or new substance exposes a weakness, review the plan even where the three-month trigger needs a closer legal and factual assessment. Emergency readiness should not depend on waiting for an anniversary date.

Which changes count?

The regulation names three categories: person, procedure and action specified in the plan. A named spill leader, an instruction for how to summon emergency services or the sequence for protecting nearby workers are straightforward examples if they appear in the plan. The legal question is not whether any document was edited. It is whether one of these specified operational elements changed.

A spelling correction in a document may have no bearing on the test function. A new person taking responsibility for a response role does. Moving a contact telephone number may or may not amount to a procedure change, depending on what the plan actually says and how emergency contact is organised. If uncertainty matters, it is usually simpler to test the affected function than to argue that a material response change was merely administrative.

Review the current plan and its revision history. Identify the exact person, procedure or action changed, the previous arrangement and the new one. Do not rely solely on a generic change ticket such as “ERP updated.” A reader of the test record should be able to see why the test occurred and what it had to demonstrate. The current law specifies that a new person must be able to perform their functions and that a new procedure or action must be workable and effective.

If several operational elements change together, plan one coherent exercise that covers each changed function. A new coordinator may need to use a revised call-out sequence and direct a different spill-control procedure. Testing only that the coordinator can answer a telephone may leave the material procedure untested. Set the test objectives from the actual plan changes and reasonably foreseeable emergency scenario.

Use the plan to design the test

The test is not just proof that a file exists. Regulation 5.7 describes substantial plan content. It calls for actions to warn people, advise them how to protect themselves, help injured people, manage the emergency and re-establish controls. It identifies responsibilities, contact routes, skills and training. It also calls for information on hazardous properties and controls, emergency-service contact, equipment and facilities, an inventory and, where applicable, a site plan.

Select a realistic scenario from the reasonably foreseeable emergencies the plan covers. For a flammable-liquid store, the exercise might examine alarm, isolation, people at risk and emergency-service contact. For a corrosive-liquid transfer area, it might focus on warning, immediate protection, spill-control equipment and the limits of what workers are trained to do. These are illustrations for test design, not directions to untrained people to tackle a dangerous incident.

Start with the changed function. If a person changed, can that person be reached, understand the role, use the available information and make the required hand-offs? If a procedure changed, can the relevant workers find it and follow its sequence? If an action changed, is the equipment present and can the action be performed under realistic conditions? A test may be a tabletop exercise, a practical drill or a combination appropriate to the risks and functions. The regulation states the outcome to demonstrate, not a mandatory one-size-fits-all drill format.

Include shifts and people who would actually be present. A daytime exercise cannot automatically demonstrate that the night shift can access the plan and summon the same help. Test communication across shared workplaces or contractors when the plan relies on them. If the plan assumes Fire and Emergency New Zealand will perform a particular role, check that the assumption is realistic. WorkSafe notes that Fire and Emergency New Zealand can review a plan. Do not present its optional review as a substitute for the PCBU's test duty.

Protect people during the exercise

A test must not create the emergency it is meant to prepare for. Establish the exercise boundaries and the simulated elements before it begins. Identify any equipment that will be handled and any process that must remain in its normal safe state. Do not release hazardous substances or disable a necessary control merely to make the exercise feel realistic.

Tell participants and other affected people what part of the event is simulated. If a live alarm is used, coordinate to prevent confusion with a real emergency. If emergency services are involved, agree their role before the exercise. The safest format depends on the workplace, substances and capability of participants. Where the plan calls for specialist response, a test can examine recognition, withdrawal, isolation and communication rather than asking ordinary workers to perform a specialist intervention.

Give observers a clear checklist of the functions being demonstrated. Note not only elapsed time but whether the correct people were contacted, hazard information was available, equipment could be found and decisions followed the plan. A quick test that skips a crucial hand-off is not necessarily an effective test. The measure is whether the plan works for the event it claims to cover.

Keep normal emergency arrangements active during the exercise. A real spill or injury can occur while a drill is underway. Participants should know how to distinguish and respond to an actual incident. The exercise plan itself is a practical process document, not a claim that the hazardous-substances regulation dictates a specific drill form.

Record the test and its result

Regulation 5.12, subsections 4 and 5 require the PCBU to make a record of tests and their results and to keep each record for at least two years after it was made. The law does not prescribe a branded template. A useful record should be clear enough to show what was tested, what happened and what followed.

Record the test date and location, the version of the plan, the trigger, the scenario, participating roles, the changed person, procedure or action, observations, outcome and any corrective action. Make the distinction between a successful step and one needing improvement explicit. If a person could not access the inventory or equipment, record the actual failure rather than changing the record to say “passed with comments.”

Keep evidence proportionate. A short record of a focused call-out test may be adequate if it captures the function and result. A complex multi-area drill needs more detail. Photos, sign-in records and timestamps can support the account, but do not replace a finding about whether the plan was workable and effective. Protect personal information in line with the organisation's normal records practice.

Connect the record to the revision it tested. If a response leader is changed again, the old test does not prove the new leader can perform the role. If a procedure is subsequently rewritten, identify the date of that change and schedule the relevant retest. A folder full of drill sheets without a plan-version link makes it difficult to know which arrangements were actually exercised.

Act on what the test finds

Subsection 3 of Regulation 5.12 requires a PCBU, so far as is reasonably practicable, to amend the emergency response plan in response to test findings so that it is workable and effective. A test that reveals a blocked exit, an unreachable coordinator or an unavailable spill kit has not completed its practical purpose when the form is filed. Assign an owner and date for the correction, then check that the changed arrangement works.

The legal text does not say that every test finding automatically demands the same corrective measure. An observation may call for a document correction, a training change, equipment repair or a revised response sequence. Assess what the finding means for the hazards and the plan. Where the change alters a plan-specified person, procedure or action, consider the subsection 2 retest clock for the new arrangement rather than assuming that the original failed exercise tested the later fix.

Tell affected workers and other people who rely on the plan about material changes. Replace old instructions where they may still be used. If a contractor's role changes, agree the hand-off with that contractor instead of changing a name in the PCBU's copy alone. A realistic retest should confirm that the corrected arrangement is available on the shifts and at the locations where an emergency might arise.

Keep the annual testing programme moving while the correction is made. The three-month change trigger and 12-month routine test are separate checks on continuing readiness. Neither turns an unsafe interim arrangement into an acceptable one simply because a future date is on a calendar.

If the substance inventory changes

A new hazardous substance, increased quantity or changed storage layout can affect whether an emergency plan is required and what it must cover. Regulation 5.6 sets the applicability test through classifications, forms and quantities. Regulation 5.7 requires the plan to address reasonably foreseeable emergencies involving substances present or likely to be present. These duties make an inventory change relevant to the plan, even though the literal three-month testing trigger names changes to a plan-specified person, procedure or action.

Ask two questions in sequence. Does the changed stock alter the subpart's applicability or the emergency scenario the plan must cover? If so, update the plan and the associated information. Then ask whether that update changes a specified person, procedure or action. If it does, the three-month test rule applies to that change. A significant new scenario may also justify prompt testing as a prudent safety step even where the legal trigger is not neatly expressed as a changed named role or procedure. Do not label this broader prudent step as the precise wording of subsection 2.

The WorkSafe emergency-plan page outlines information the plan should contain, including the inventory, site plan, people involved and equipment. Use the actual updated inventory and workplace map when revising the plan. An annual drill based on substances no longer present may show that an old plan once worked. It does not answer whether the current plan addresses today's hazards.

If the new stock changes a threshold calculation, check the current official Schedule 5 and any relevant special rule. Avoid copying a quantity from a generic blog or an old SDS. Product classifications and quantities can be site-specific. A business with unusual substances or mixed storage may need specialist assistance with classification or emergency design. This article provides the process and source boundary, not a site-specific threshold determination.

Keep emergency planning and ordinary control reviews distinct

Hazardous-substances risk control duties exist even where a site does not cross the emergency-plan threshold. The wider 2017 Regulations contain inventory, SDS, labelling and risk-management provisions. A business should not read “no Subpart 2 ERP required” as “no chemical emergency preparation needed.” Other general workplace emergency duties can also apply. Identify the actual regime rather than folding them into one unqualified statement.

An emergency response plan is a response to foreseeable loss of control. It does not replace prevention. Review containment, segregation, training, access and maintenance alongside the response arrangements when the workplace changes. A test may reveal that the response is too dependent on a control that is unavailable, but the answer can include improving the underlying control as well as rewriting the plan.

Do not confuse an ERP test with a hazardous-substance inventory review. The inventory supports the plan and emergency services. A changed inventory may require a plan review, while the test demonstrates whether the people and actions in the resulting plan are workable. Keep the evidence for each purpose clear. This prevents one completed checklist from being used to imply that all relevant controls have been assessed.

A workable decision sequence

When an ERP-related change is reported, begin by confirming that the site falls within Subpart 2. Identify the current plan version and the exact changed element. If it is a plan-specified person, procedure or action, record the change date and arrange a test within three months. Set test objectives that match the changed function, while checking whether the annual test is also due.

Run a safe exercise proportionate to the hazards. Observe what the participants can actually do. Record the test and results, retain the record for at least two years, and assign corrective actions. Amend the plan in response to findings so far as reasonably practicable. Communicate material changes and test the corrected function where needed. Keep the next annual test on the programme.

This sequence is an operational way to carry out Regulation 5.12, not a claim that the law requires a particular software workflow or form. The plan still needs to suit the real substances, site and people. If a practice exercise reveals a genuine emergency-readiness gap, address it as a safety issue rather than merely preserving the test date.

For a wider introduction to New Zealand hazardous-substances duties, read the existing Complys overview. If you are evaluating how to organise your compliance work, the Complys New Zealand page is a neutral place to start. Confirm any specific product capability with the product team. This article makes no claim that Complys schedules, conducts or legally validates ERP tests.