Responding to Chemical Spills: Spill Kits and Steps

Chemical spill response: classify first

The most critical moment in a chemical spill response is the first minute, and the decision to be made in that minute must have been written down in advance: is the incident a minor spill that trained workers in the section can safely clean up with a spill kit, or a release that requires the area to be evacuated and emergency teams to step in? Everyone responding with cloths and buckets without making this distinction is the most common and most dangerous mistake.

Classification criteria are set in the workplace's emergency plan according to the substance and quantity. The table below is a starting point:

Criterion	Minor spill	Release requiring evacuation
Substance	Identity known, SDS accessible	Identity unknown or mixture uncertain
Quantity	Within the capacity of the spill kit	Exceeds kit capacity, or the source cannot be stopped
Vapour and odour	No noticeable vapour, slight odour	Vapour or gas causing watering eyes or breathlessness
Fire and explosion	Not flammable, or no ignition source	Flammable substance and an ignition source nearby
Spread	In a tray or a small area	Reaching the sewer, the stormwater line or outside
People affected	No one affected	Someone exposed or injured
PPE required	The PPE in the kit is sufficient	Respiratory protection or full protective clothing needed

If even one of the criteria in the right-hand column applies, the incident is treated as a release requiring evacuation. When in doubt, it is also treated as a major incident: the cost of needlessly treating a minor spill as major is far lower than the cost of treating a major release as minor.

Spill kits: what should they contain?

The spill kit should be kept close to where the chemical is used and stored, in an easily accessible and marked place. The kit contents are chosen according to the SDSs of the chemicals at that point:

Absorbent material: Pads, rolls, socks that act as barriers and granular absorbent. There are different absorbents for general purpose use, for oil and hydrocarbons only, and for aggressive chemicals such as acids and bases; choose the right type.
Neutraliser: At points where acid or base spills may occur, the neutralising agent recommended in the SDS.
Drain cover: A cover or plug that quickly seals a floor drain and prevents the chemical from entering the sewer.
Non-sparking shovel and broom: An essential detail for flammable liquids.
Waste bags and a lidded container: Together with a hazardous waste label.
PPE: Chemical-resistant gloves, safety goggles or a face shield, an apron or coverall, and boots and suitable respiratory protection if needed. The type is determined by Section 8 of the SDS.
Warning tape or warning sign: To cordon off the area.
Contents list and instructions for use: On the kit lid, with the date of the last check.

Response sequence for a minor spill

The chemical spill procedure should be simple enough for a trained worker to apply without having to think about the order:

Warn: Warn nearby workers and inform the supervisor and the person responsible for emergencies.
Identify: Look at the container label and open Section 6 of the SDS (accidental release measures). If the substance is unknown, stop: this is no longer a minor spill.
Protect yourself: Put on PPE as per the SDS. Have a second person with you.
Remove ignition sources: If it is a flammable liquid, switch off nearby heaters, spark-producing equipment and open flames.
Stop the source: Set the overturned container upright, close the valve, put the leaking package in a lidded overflow tray.
Contain the spread: Seal the floor drain with a drain cover and surround the spill with absorbent socks.
Absorb and collect: Apply absorbent from the outside inwards; once it has absorbed, collect it with a non-sparking shovel and put it in the waste bag.
Clean: Clean the area as recommended in the SDS; treat the cleaning water as waste too.
Record: Report the incident as a near miss or incident record; find the cause.

The last step is often skipped. Yet every spill shows that a package, a transfer method or a shelf is problematic. For the reporting arrangements, see our article on the near miss reporting system.

Chemical spill evacuation: what to do in a major incident

In a major release, the workers' task is not to clean up but to move away and provide information. Article 8 of the Regulation on Health and Safety Measures in Work with Chemical Substances sets the following rules for this situation:

Measures to reduce adverse effects are taken immediately and workers are informed of the situation.
Only workers assigned for maintenance, repair and essential work, and teams coming from outside, enter the affected area.
These persons are given suitable PPE and special safety equipment; no one without suitable equipment is allowed to enter the area.
Information on hazardous chemicals and emergency procedures is kept ready, and easy access to it is ensured for the workplace's own teams and for external first aid, rescue and fire brigade teams.

In practice, evacuation works like this: the alarm is raised, workers go to the assembly point by the planned route and in the direction the wind carries away from the release, a headcount is taken, and 112 is called. The person responsible for emergencies hands the arriving teams the name of the substance, its quantity, the SDS and a sketch showing the location of the release. No one goes back saying "it looks small".

Absorbent material and waste disposal

Absorbents, cloths and used PPE that have soaked up chemicals are not ordinary rubbish. In the Annex 4 waste list of the Regulation on Waste Management, code 15 02 02* covers absorbents, filter materials, wiping cloths and protective clothing contaminated by hazardous substances; packaging containing residues of or contaminated by hazardous substances is coded 15 01 10*. Codes marked with an asterisk in the list indicate hazardous waste.

Step	Rule
Collection	The waste is collected in a separate container without being mixed with other wastes it could react with
Labelling	The container carries the words "hazardous waste", the waste code, quantity and storage date
Temporary storage	Hazardous waste is stored temporarily at the site where it was generated for a maximum of 6 months
Handover	It is handed over, with records, to a licensed transport and disposal or recovery company

Washing contaminated absorbent into the sewer, throwing it in household rubbish or leaving it in the open turns an occupational safety problem into an environmental one.

Prevention: arrangements that reduce spills

The best response is the one that is never needed. In chemical and plastics businesses, dyehouses and maintenance workshops, typical high-risk points for spills are drum-to-drum transfers, forklift transport, shelf edges and filling points. At these points, the following arrangements reduce the risk of leaks:

Overflow tray: Liquid chemical containers sit on a tray or bunded shelf with a volume that can hold the entire contents of the largest container. The tray keeps a leak within the minor spill category.
Separation by compatibility: Acids, bases, oxidisers and flammables do not share the same tray; if they have to be next to each other, there is physical separation between them.
Transfer method: A hand pump or dosing pump is used instead of tipping the drum to pour; intermediate containers are labelled. An unlabelled container means a substance of unknown identity during a response.
Transport: Drums and IBCs are secured on the forklift, damaged pallets are not used, and speed is reduced in chemical store aisles.
Floor drains: Where drains in areas where chemicals are used are connected to is known and shown on the plan; where possible, a floor without drains is preferred.

These arrangements should be included in the risk assessment and checked during periodic site inspections.

Drills and training

A spill kit only works if someone knows how to use it. Your emergency plan should include a chemical spill scenario, and one of the drills held at least once a year should use this scenario. In the drill, test in particular: who made the classification decision and how quickly; was the drain cover in place; how many minutes did it take to reach the SDS?

For preparing the plan, see our article on how to prepare an emergency plan; for designing the scenario, emergency drills; and for Sections 6 and 8 of the SDS, how to read a safety data sheet. You can enter drill and kit check dates in the OHS calendar. For a plan prepared according to chemical risk, see our emergency plan service, and for risks specific to your sector, our chemicals and plastics page.

Frequently Asked Questions

What should a spill kit contain?

Absorbent pads, socks and granules; neutraliser if needed; a drain cover; a non-sparking shovel; waste bags and labels; gloves, eye protection and an apron suited to the chemical; warning tape and a contents list. The contents are chosen according to the SDSs of the chemicals at that point.

Is it right to wash a chemical spill away with water?

Usually not. Water spreads the chemical and can carry it into the sewer; some substances react with water. First look at Section 6 of the SDS; in most cases, the right method is to contain the spread and collect it with a suitable absorbent.

How is contaminated absorbent disposed of?

It is collected as hazardous waste in a separate, labelled container, stored temporarily at the site for no more than 6 months and handed over to a licensed company. Its code in the waste list is 15 02 02*.

Who can respond to a minor spill?

Workers who know the chemical, have been trained in the use of the spill kit and have suitable PPE. Other workers' task is to leave the area and raise the alarm.