Guidelines

Chemical Storage Safety - Guidelines

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1.0    Purpose and Scope 

This guideline provides information about the safe storage of chemicals at The University of Queensland (UQ) and applies to:

  • UQ workers (as defined in the appendix) involved in the storage of chemicals at UQ; and

  • storage or handling systems which are bottles, packages, cylinders, drums, carboys, intermediate bulk containers (IBCs), tanks, vessels, reaction vessels, blending and mixing equipment, and associated pipework and connections.

The information in this guideline is intended to help UQ workers understand their obligations and apply the recommended procedures for bottles, packages, cylinders, drums, carboys and intermediate bulk containers (IBCs), which are the most common storage or handling systems at UQ sites, especially in laboratories, workshops and other areas where chemical containers are open.

1.1 Relevant standards and legislation

This guideline should also be read in conjunction with other UQ procedures and guidelines regarding  Occupational Hygiene and Chemical Safety, including Storage of Chemicals in Fridges, Freezers and Cold Rooms and Storage and Handling of Gas Cylinders.

2.0    Summary

UQ Organisational Units are responsible for prioritising the safe storage of chemicals and managing risks associated with the use, handling, production, disposal and storage of hazardous chemicals – in accordance with the WHS Regulation.

UQ workers should consider the following matters to support the safe storage of chemicals at UQ:

  1. Identifying hazardous chemicals and knowing how to store them and other chemicals.

  2. Understanding incompatibly storage issues and segregating chemicals accordingly.

  3. Storing chemicals under the right conditions.

  4. Minimising the potential for chemicals to become unstable, decompose or change during storage as it represents a different hazard (e.g., time-sensitive chemicals require especial precautions and monitoring, temperature control might apply).

  5. Monitoring the integrity of the chemical labelling, packaging, seals and containers.

  6. Minimising quantities of hazardous chemicals, commensurate with their usage and shelf life, and within the permitted storage limits.

  7. Securing structures or plant used for the storage of hazardous chemicals are secured and fixed to stable foundations and measures are in place to prevent or control impact to containers, structures or plant containing hazardous chemicals.

  8. Regularly reviewing chemicals held in storage and correctly disposing of those no longer required using the UQ waste procedures or via the UQ Science Store.

  9. Attending required health and safety training, especially regarding chemical use, emergency response and first aid response.

  10. Reporting any incidents or near misses to a supervisor and in UQSafe.

3.0    Identifying for safe storage

Hazardous chemicals and dangerous goods are a risk to the safety and health of people and the environment in the workplace. Workers need to be able to identify and avoid those risks, to avoid harmful exposure and impacting the environment. Education, induction, training, and supervision allows for the acquisition of knowledge on how to identify hazardous chemicals. Another tool available to workers are Safety Data Sheets (SDS) as they will identify the hazardous nature of a chemical. At UQ SDSs they are available through Chemwatch, or directly from manufacturers and suppliers. Refer to the Safety Data Sheets Guideline for further information.

Workers need to complete risk assessments when working with chemicals and include the requirements for storage.

Workers need to have clear signage on chemical storage area entry doors to identify chemical classes contained within the laboratory, workshop or area.

4.0    Segregation for safe storage

Store chemicals according to their Dangerous Goods (DG) class and segregate from incompatible classes. Any secondary dangerous goods class classification must receive consideration for further segregation if reasonably practicable. There is no minimal segregation distance, provided there is sufficient control to prevent two incompatible chemicals directly mixing in the event two containers break at the same time.

Refer to the Workplace Health and Safety Queensland Segregation tool, for further information. Safety data sheets (SDS) available through Chemwatch also provide information on appropriate segregation and storage.

The Global Harmonised System (GHS) and the DG classification differ and must be understood by the users. For example, the flammable GHS classification/pictogram covers several Dangerous Goods classes (DG 2.1, DG 3, DG 4.1, DG 4.2, DG 4.3 and DG 5.2) as shown in Table 1, which need segregation. Also refer to the national guide Safe Work Australia classifying hazardous chemicals and Appendix G of the Safe Work Australia model code of practice of Labelling Workplace Hazardous Chemicals.

Table 1 - Comparison of GHS pictogram with ADG class ones

Further clarification can be obtained from the HSW Manager or the Workplace Health and Safety Coordinator (WHSC) in your area, the Occupational Hygiene Advisor in the HSW Division, or at the HSW Division.

5.0    Chemicals requiring special storage conditions

Store hazardous chemicals, so far as is reasonably practicable, under the right conditions to ensure their integrity. Hazardous chemicals must not become unstable, decompose or change so as to create a hazard different to the hazard originally created by the hazardous chemical, or significantly increase the risk associated with their hazardous properties.

Some hazardous chemicals are inherently unstable or highly reactive or can become
unstable under certain conditions. For example:

  • Substances which are unstable at ambient temperature must be kept in a controlled temperature environment set to maintain an appropriate temperature range. Reliable alternative safety measures must be provided for situations when utilities such as power, fail. Substances that can present additional hazards on heating should be clearly identified.

  • Sunlight can affect some plastic containers or the chemical contents. Containers or chemicals that are photosensitive should not be stored where they can be exposed to direct sunlight.

  • Chemicals such as hypochlorite solution and NoChromix glassware cleaner decompose to produce gaseous products and must be stored in vented cap containers. Ensure a vented cap container is used if decanted from the original manufacturer packaging. Vented cap containers must be stored in an upright position, otherwise venting of gaseous products will not take place.

  • Flammable or combustible chemicals, oxidising agents and/or the presence of other activities or materials can present significant risk of fire or explosion.  Hazardous atmospheres and hazardous areas should be assessed; ignition sources must be eliminated from any hazardous areas; and auto-ignition temperatures should be considered as some hazardous chemicals may ignite spontaneously about certain temperatures.

Other chemicals require restricted access and extra security controls:

5.1    Aerosols

Aerosol cans are classified as Class 2 Dangerous Goods, e.g., Gases. Aerosols of Divisions 2.1 Flammable gases and 2.2 Non-flammable, non-toxic gases may be stored in a store for Class 3 dangerous goods store if projectile protection is provided. Aerosol cages that comply with AS4332: The Storage and Handling of Gases in Cylinders meet this requirement. If projectile protection cannot be provided, aerosols must be segregated from flammable liquids by 5 metres. Given this distance must be calculated from the edge of the spill catchment area, aerosols will under most circumstances need to be stored in a separate room, or in an aerosol cage as described.

5.2    Flammable and combustible liquids

Flammable and combustible liquids must be handled and stored to minimise the fire risk.  See Flammable and Combustible Liquids: Storage and Handling - Procedure for further information.

5.3    Storage of time-sensitive chemicals

Time-sensitive chemicals are those chemicals that, when stored for prolonged periods or under poor storage conditions, may develop hazards that were not present in the original formulation. There are four general categories of time-sensitive chemicals loosely based on those unsafe properties that can develop, such as:

  • peroxide formers: Oxygenated organic compounds that react with atmospheric oxygen to form explosive peroxides. Examples commonly found in laboratories include sodium amide, diethyl ether, dioxane, THF, and benzyl alcohol;

  • peroxide formers that can undergo hazardous polymerization such ethyl ether and sec-butyl alcohol;

  • materials that become shock or friction sensitive upon the evaporation of a stabilizer. Examples include azides, nitrate esters and picric acid; and

  • materials that generate significant additional hazards by undergoing slow chemical reactions, like Chloroform that reacts with air over time to form phosgene, a deadly gas with similar to new-mown hay odour, and isopropyl alcohol (2-propanol) forms peroxides very slowly.

It should be noted that time-sensitive chemicals can be pure reagents or they can be commercial mixtures formulated as cleaners, adhesives and other products.

All time-sensitive chemicals should be immediately marked with an expiration date upon receipt and listed on the laboratory chemical inventory to ensure timely disposal. The SDS for the chemical will state whether it is unstable under certain conditions or after a period of time in storage, and this information should be highlighted in the risk assessment. If the appearance of the chemical changes this is often a sign that the chemical should be quenched or sent for disposal.

Containers should be inspected periodically, with a frequency determined by a risk assessment, to verify their condition. Signs of peroxide formation include crystal formation in the container, discoloration of liquids, or a “mossy” appearance around the cap. Peroxide test kits (strips) can also be used to determine peroxide concentration before a container is moved.

If suspect materials are recognised, do not handle the container. Particularly, do not attempt to remove the cap. If explosive crystals have formed around the cap, the friction created by the unscrewing of the cap may be enough to detonate the compounds. Further advice can be obtained from an Occupational Hygiene Consultant or the local Workplace Health and Safety Coordinator.

Refer to Table 2 (Chemical Health and Safety, Vol. No. 3, No. 5, “Review of Safety Guidelines for Peroxidizable Organic Chemicals", September/October 1996, pp. 28-36; and guides by University of California-Berkeley and Baylor University).

Table 2 – Time-Sensitive Chemical Types

A - Chemicals that form explosive levels of peroxides without concentration (3 months)1

Butadiene2 (106-99-0)

Isopropyl Ether (108-20-3)

Tetrafluoroethylene2 (116-14-3)

Chloroprene2 (126-99-8)

Potassium Metal (7440-09-7)

Vinylidene Chloride (75-35-4)

Divinyl Acetylene (821-08-9)

Sodium Amide (7782-92-5)

 

B - Chemicals that form explosive levels of peroxides on concentration (12 months)1

1,1-Dimethoxymethane (109-87-5)

Benzyl alcohol (100-51-6)

Di-n-propoxymethane (505-84-0)

1,2-Epoxy-3-isopropoxy propane
(4016-14-2)

Benzyl n-butyl Ether (588-67-0)

Dioxane (123-91-1)

1,2-Dibenzyloxyethane (622-22-0)

Benzyl Ether (103-50-4)

Diethyl Ether (60-29-7)

1-Phenylethanol (98-85-1)

Benzyl Ethyl Ether (539-30-0)

Ethylene Glycol Dimethyl Ether (110-71-4)

2-Butanol (78-92-2)

Benzyl 1-naphthyl Ether (607-58-9)

Isoamyl Ether (544-01-4)

2-Hexanol (626-93-7)

Cumene (98-82-8)

Isophorone (78-59-1)

2-Methyl-1-butanol (137-32-6)

Cyclohexene (110-83-8)

Methyl Isobutyl Ketone (108-10-1)

2-Penten-1-ol (1576-95-0)

Cyclooctane (292-64-8)

Methyl Acetylene (74-99-7)

2-Phenylethanol (60-12-8)

Decahydronapthalene (91-17-8)

Methylcyclopentane (96-37-7)

2-Propanol (67-63-0)

Diacetylene (460-12-8)

Other secondary alcohols (N/A)

4-Heptanol (589-55-9) p-

Diallyl Ether (557-40-4)

Dibenzyloxybenzene (621-91-0)

4-Methyl-2-pentanol (108-11-2)

Dicyclopentadiene (77-73-6)

p-Isopropoxypropionitrile (110-47-4)

4-Penten-1-ol (821-09-0)

Diethoxymethane (462-95-3)

Tetrahydrofuran (109-99-9)

Acetal (105-57-7)

Diethyl acetal isoamyl benzyl ether (N/A)

Tetrahydronaphthalene (119-64-2)

Acetaldehyde (75-07-0)

Diethylene Glycoldimethyl Ether
(diglyme) (111-96-6)

Vinyl Ethers (N/A)

Allyl Ether (557-40-4)

Dimethoxymethane (109-87-5)

 

C - Chemicals that may autopolymerize as a result of peroxide accumulation (12 months)1,3,4

Acrylic Acid (79-10-7)

Methyl Methacrylate (80-62-6)

Vinyl Chloride (75-01-4)

Acrylonitrile (107-13-1)

Styrene (100-42-5)

Vinylidene chloride (75-35-4)

Butadiene2 (106-99-0)

Tetrafluoroethylene2 (116-14-3)

2-Vinyl Pyridine (100-69-6)

Chloroprene2 (126-99-8)

Vinyl Acetate (108-05-4)

4-Vinyl Pyridine (100-43-6)

Chlorotrifluoroethylene (79-38-9)

Vinyl Acetylene (689-97-4)

 

D - Other Time Sensitive Chemicals (varies)5

Acetylene (74-86-2)

Ethylene oxide (75-21-8)

Nitrogen triiodide (13444-85-4)

Ammonium Nitrate (6484-52-2)

Germanium (7440-56-4)

Nitrogen trichloride (10025-85-1)

Ammonium Perchlorate (7790-98-9)

Hexanitrodiphenylamine (131-73-7)

Nitroglycerin (55-63-0)

Ammonium Picrate (131-74-8)

Hexanitrostilbene (20062-22-0)

Nitrogylcol (628-96-6)

Calcium Nitrate (10124-37-5)

Hydrazine (302-01-2)

Nitroguanidine (556-88-7)

Chloroform (67-66-3)

Hydrazoic acid (7782-79-8)

Nitrourea (556-89-8)

Dinitrotoluene (121-14-2)

Hydrogen Compound Gases (NA)

Perchloric acid (7601-90-3)

Dinitrophenol (51-28-5)

Lead styphnate (15245-44-0)

Picric acid (88-89-1)

1. Safe storage periods are given for an open container of each class of peroxidizable material. Unopened containers from the manufacturer have a safe storage period of 12 months.

2. When stored in liquid form these chemicals may form explosive levels of peroxides without concentration. When stored as a gas, these chemicals may autopolymerize as a result of peroxide accumulation.

3. If chemical from list C is inhibited, do not store under an inert atmosphere. Oxygen is required for inhibitor to function.

4. Uninhibited chemicals from list C have a safe storage period of 24 hours.

5. Please refer to the SDS and manufacturers’ information for more details on safe storage and shelf life.

5.3.1    Time-Sensitive Compressed Gas Cylinders

The compressed gases listed below have a shelf-life provided by the manufacturer that must be strictly followed. Incidents involving these compounds usually relate to storage past the expiration date. For example, hydrogen fluoride (HF) and hydrogen bromide (HBr) cylinders have a shelf-life of one to two years, depending on the vendor. Over time, moisture can slowly enter the cylinder, which initiates corrosion. As the corrosion continues, HF and/or HBr slowly react with the internal metal walls of the cylinder to produce hydrogen. The walls of the cylinder weaken due to the corrosion, while at the same time the internal pressure increases due to the hydrogen generation. Ultimately, these cylinders fail and create extremely dangerous projectiles and a toxic gas release.

  • Hydrogen fluoride, Anhydrous

  • Hydrogen bromide, Anhydrous

  • Hydrogen sulfide, Anhydrous

  • Hydrogen cyanide, Anhydrous

  • Hydrogen chloride, Anhydrous.

5.4     Storage of air-sensitive chemicals

A chemical is classed as air-sensitive if it reacts with oxygen (O2), water, nitrogen (N2), or carbon dioxide (CO2). Air-sensitive chemicals must be isolated from the atmosphere and handled in a controlled environment. Typically, under an atmosphere of nitrogen or argon. This comes in a suitably pure form from a cylinder fitted with an appropriately sized regulator. Nitrogen, less expensive, is usually the preferred gas unless the chemical(s) under study react with nitrogen.

Figure 1 - Examples of compounds that oxidize, decompose, or explode under the influence of oxygen or moisture.

The best way to keep things away from atmospheric oxygen and water is to work in a glove box, a fully enclosed bench top cabinet containing an inert atmosphere, which one could reach into with gloves. Air-sensitive chemicals can also be stored in a dry box. There are also glove bags (AtmosBag), a poorer substitute, which you can fill with inert gas and reach into with attached gloves. Refer to Figure 2.

 

Figure 2 - Glove box (left), AtmosBag (centre) and Dry box (right).

Other techniques are the use of Schlenk apparatus or the Sure/SealTM packaging system (Septum Inlet Transfer Adapter and Oxford Storage Valve Cap).

5.5    Storage of temperature-sensitive chemicals

Many of the chemicals in storage at UQ need to be stored under relatively stable temperature and humidity regimes for best shelf life and safety. The space or plant to be used for chemical storage must be fit for purpose for the safe and secure storage of these chemicals. Take the necessary precautions to ensure that appropriate storage happens from arrival to disposal (e.g., to lower the risk of explosion).

5.5.1    Storage of chemicals in refrigerators, freezers or cold rooms

Where flammable substances are to be stored in refrigerators, a pharmaceutical fridge or freezer with a spark proof interior must be purchased. Refer to Storage of Chemicals in Fridges, Freezers and Cold Rooms Guideline.

Controlled substances that require refrigeration will need to be secured in safes, lockable cash boxes inside fridges, freezers or cold rooms; or made secure by a lockable door or mechanism. Refer to other Occupational Hygiene and Chemical Safety Procedures and Guidelines.

6.0    Chemical packaging and labelling

When storing chemicals, ensure the containers and their seals or stoppers are appropriate for the type and quantity of chemical stored. As far as is practicable, chemicals should be stored in the containers in which they are supplied and kept closed when not in use. Decanted chemicals must also be labelled appropriately during storage, refer to the Chemical Labelling Guideline.

Packages should be inspected regularly, at least annually, to ensure their integrity and the labelling remains legible. Leaking or damaged packages should be removed to a safe area for repacking or disposal. Labels must be reattached or replaced, as necessary, to clearly identify the contents of the package.

7.0    Storage limits

AS/NZ 2243.10 Safety in Laboratories: Storage of Chemicals, states the following quantities of chemicals are permitted to be stored in a laboratory, other than in a chemical storage cabinet (e.g., open bench storage), refer to Table 3. These limits should be followed as closely as possible, and quantities in excess of these levels should be stored in a dedicated Dangerous Goods cabinet.

Containers must be treated as full, unless the container has been emptied, cleaned and the label removed or defaced.

Any individual chemical container must be ≤25 L, even when stored in a Dangerous Goods cabinet (this includes chemical waste containers).

The ventilation within a laboratory must be suitable to ensure any flammable vapours do not exceed 5% of the applicable lower explosive limit (LEL) and any toxic vapours must not exceed the relevant workplace exposure standard. This includes when chemical containers are opened for decanting or other use. Depending on the volatile nature of the chemicals in use, this may be achieved via either natural or mechanical ventilation, see Section 5 of AS/NZS 2982 for further specifications. Each laboratory must have a dedicated ventilation system not shared by other storage areas, and exhaust air must discharge outside the building.

For a workshop, the ventilation must be adequate to prevent the build-up of a hazardous atmosphere.

Table 3 - Quantities of hazardous chemicals permitted to be stored in a laboratory working area outside of a Dangerous Goods Cabinet for AS2243.10.

Type of Goods

Maximum quantity per 50m2 (kg or L)

Maximum container size (kg or L)

Notes

Conditions of storage

Alternative storage options

Class 3 (primary or subsidiary risk)

10

5

A chemical storage cabinet or cupboard used to store these liquids must not be used to store dangerous goods of any other class.

Labelled standard laboratory cupboard/cabinet or in small amounts throughout the laboratory.

AS 1940 or

AS/NZS 3833

Combustible liquid

50

20

 

Labelled standard laboratory cupboard/cabinet or in small amounts throughout the laboratory.

AS 1940 or

AS/NZS 3833

Class 4.1, 4.2, 4.3, 5.1* or 5.2

20 total, but less than 10 of any one Class

10

A chemical storage cabinet or cupboard used to store these classes dangerous goods must not be used to store dangerous goods of any other class.

E.g., a cabinet or cupboard containing Class 4.1 may only contain Class 4.1 goods.

Labelled standard laboratory cupboard/cabinet or, for Classes 4.1, 4.3 and 5.1,  or in small amounts throughout the laboratory.

AS 2714 or

AS/NZS 3833

Class 6.1

PG I 10

Other 50

PG I 10

Other 20

 

Labelled standard laboratory cupboard/cabinet or in small amounts throughout the laboratory.

AS/NZS 4452 or

AS/NZS 3833

Class 8

20 for liquids

50 for solids

20

Class 8 dangerous goods must be stored in a manner that will prevent reactions between:

  • acids and alkalis
  • acids and hypochlorites
  • acids and cyanides
  • oxidizing acids and combustible materials
  • incompatible acids

Labelled standard laboratory cupboard/cabinet or in small amounts throughout the laboratory.

AS 3780 or

AS/NZS 3833

Class 9 and aerosols

50 for liquids

100 for solids

5 for liquids

20 for solids

 

Labelled standard laboratory cupboard/cabinet or in small amounts throughout the laboratory.

AS/NZS 4681 or

AS/NZS 3833

Hazardous chemicals, generally

N/A

5 for liquids

20 for solids

 

Labelled standard laboratory cupboard/cabinet or in small amounts throughout the laboratory.

 

Maximum aggregate quantity

200

N/A

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

* The quantities for Class 5.1 stated in the Table are the total amount of active ingredient present, rather than the actual volume or mass to allow for the very wide differences between concentrations of active ingredient in peroxides and hypochlorites that are commonly used in laboratories.

At UQ we encourage best practice and strongly recommend hazardous chemicals to be always stored inside cabinets. Wherever possible, a reduction of stock should be implemented if materials cannot be safely stored in cabinets. Storage in open benches should be considered as a last resort, and always within the allowed limits.

There is no limit for the storage of non-hazardous chemicals.

Within a horizontal radius of 10 m, measured from any one cabinet, the aggregate storage capacity for all cabinets in that radius must not exceed 250 L or kg, including through intervening walls. Within this radius, any PG I dangerous goods from Classes 4.1, 4.2, 4.3, 5.1, 5.2 must not exceed 10kg or L for each class. An example layout is provided in Figure 3.

Figure 3 - Example layout for minimum separation distances for minor storage.

8.0    Storage structures

8.1   Chemical storage in cabinets

Dangerous Goods cabinets are commonly used to store hazardous chemicals as they provide greater protection to the chemicals stored within them in an emergency situation, e.g., spills and fires. Chemical storage cabinets for the storage of dangerous goods are required where the storage quantities exceed those listed in the table above. The cabinets should comply with the design requirements of AS1940 The storage and handling of flammable and combustible liquids, or the design criteria in the relevant standard.

The following requirements apply to the storage of chemicals within cabinets at UQ:

  • Have signage indicating the class of Dangerous Goods stored within the cabinet.

  • When storing flammable substances, the contents of the cabinet must not exceed 100L. If a 250L cabinet is used for the storage, it must be de-rated to 100L. This involves removing some of the shelving and placing a sticker over the manufacturer’s capacity rating, so that it is clear that 100L is the maximum cabinet capacity.

  • All new installations of chemical storage cabinets must incorporate mechanical extraction ventilation where highly corrosive, toxic or volatile chemicals are being stored, unless an assessment of the risk of exposure deems it not necessary. The ventilation must be to an external atmosphere (e.g., outside the building) in a manner that allows safe dispersal of vapours, fumes or dust.

  • The capacity of any chemical storage cabinet used in a laboratory to store chemicals of dangerous goods classes 4.1, 4.2, 4.3, 5.1 or 5.2 must not exceed 50L.

  • Within a radius of 10m, measured from any one cabinet, the cabinet storage capacity aggregated for all cabinets in that radius must not exceed 250L or 250kg, including no more than 10L or 10kg each of dangerous goods classes 4.1, 4.2, 4.3, 5.1 or 5.2 that are classified as PGI. The radius is measured horizontally through intervening walls, unless those walls are able to prevent the spreading of a fire of the magnitude that could be expected to result from the contents of the cabinet(s). Refer to Figure 1.

  • Dangerous Goods cabinets containing chemicals with a primary or subsidiary risk of Class 3, 4 or 5 must not be located within 3 m of an ignition source unless a hazardous zone assessment has been completed.

  • Have doors which are self-closing, close-fitting and held shut automatically by catches at two or more points. Where doors have a mechanism to hold them open, the mechanism will automatically release above 80°C.

  • Cabinets containing Class 5.2 Dangerous Goods must have doors with a self-closing mechanism as per Australian Standard 1940 section 4.9.2, but the cabinet door shall have a door closing mechanism that allows the door to open and pressure resulting from accelerated decomposition to be released, e.g., a magnetic lock or friction lock.

  • Dangerous Goods cabinets containing chemicals must be separated by a minimum distance of 250 mm of clear air space.

  • The spill catchment/bund of cabinets must not be used to store chemicals.

  • Where possible, store chemicals on chemically resistant spill trays within cupboards or cabinet. Refer to Figure 4.

Figure 4 - Example of spill tray use in storage cabinets.

  • Chemicals must not be opened or used on top of a Dangerous Goods cabinet.

  • Cabinets shall not be located:

    • One above the other.

    • Where they can jeopardize emergency escape (minimum 3m away from emergency exits or egress points).

    • Under stairs or in corridors.

8.2    Chemical storage in shelves, racks or cupboards

Other cabinets or cupboards which do not meet the specifications of Dangerous Goods cabinets may be used to store chemicals, provided:

  • The cabinet is made of a material which is resistant to spills, leaks or vapours from the chemicals enclosed. For example, cabinets made of metal or using metal supports or shelving should not be used to store chemicals which give off corrosive vapours as the metal will corrode over time.

  • Secondary containment in the form of bunded trays is used.

  • Cabinets do not enable the build-up of hazardous atmospheres such as toxic vapours.

  • Cabinets have signage indicating the class(es) of Dangerous Goods stored within them.

  • If a cabinet is used to store volatile chemicals which present an inhalation risk, ventilation must be considered. If an individual cabinet is vented, the ventilation must be to an external atmosphere (e.g., outside the building) in a manner that allows safe dispersal of vapours, fumes or dust. Each cabinet ventilation system must be completely independent (e.g., two cabinets cannot share ducting; cabinet cannot be ducted to a fume hood exhaust). 

Chemicals kept on shelves or racks are subject to the following restrictions:

  • Shelving and its fixtures must be compatible with the goods stored, or should be suitably protected from the goods (NOTE: the use of particle board is not recommended as they may fail when subjected to moisture or chemicals);

  • Secondary containment should be used to prevent spills from spreading or incompatible chemicals from mixing;

  • The maximum holding capacity of the shelving systems must not be exceeded;

  • Chemicals shall not be stored on shelves higher than 1.5m from the floor; and

  • Shelves or racks used for chemical storage should be restrained against lateral movement and must have lips on them to prevent containers being pushed through to the other side.

  • Pallets of hazardous chemicals must not be stacked on top of one another.

  • Chemical containers should not be stored on the ground.

8.3    Chemical storage room requirements

All chemical storage rooms must be purpose built and comply with the requirements of Section 5 of AS/NZ 2243.10 Safety in Laboratories: Storage of Chemicals. New buildings will generally have a dedicated Hazardous Area Classification (HAC) assessment covering the storage of flammable liquids, which may also apply to general laboratory areas as well. The HAC should be consulted when deciding the type and quantity of flammable liquids to store within a building.

On the other hand, the storage of mixed classes of Dangerous Goods in a separate store could be:

  • A separate storeroom attached to a laboratory area.

  • A chemical storage room inside a building, where laboratory work is not undertaken in the room.

  • A chemical storage room, shed, or similar, which is outside the building.

There are several Australian Standards which may be applicable to the storage of chemicals in a store separate from a laboratory, as reflected in this section. Each standard has different threshold quantities for minor storage and may include additional specific requirements for the storage area.

The most appropriate set of requirements should be selected for the storage area, using Table 4below. Once chosen, the minimum requirements for that standard must be applied in full.

Table 4 - Overview of standards which may be applied to a separate chemical storage area.

8.3.1    Seperate Chemical stores meeting AS 2243.10 requirements

In addition to the AS 2243.10 requirements for minor storage (section 3.5 and 3.6.1 to 2):

  • The store must not contain gas cylinders or cryogenic liquids.

  • Where possible the store should not contain other laboratory items such as glassware or apparatus, though the storage of other non-hazardous chemicals is permitted.

  • All internal stores should be located on the floor directly accessible from street level where possible. For stores located on any other floor of a building, a risk assessment must be conducted and documented to identify any risks posed to other floors or evacuation routes.

  • An external store must be separated from neighbouring buildings, or from site boundaries by:

    • 3 m, if the aggregate hazardous chemicals kept in the store is ≤1000 kg or L.

    • 5 m, if the aggregate hazardous chemicals kept in the store is between 1000 kg or L and 4500 kg or L.

    • No separation distance is required if fire walls or vapour screens complying with Australian Standard 1940 are installed.

  • Any individual chemical container holding liquids must be ≤100 L. This includes chemical waste containers.

  • The aggregate maximum quantities of chemicals held in the store must not exceed Table 5.

  • The maximum quantity of chemicals in any one chemical storage cabinet must be ≤100 L or kg. There are additional limitations on the quantities of chemicals in any one cabinet for some Class 5, 6 and 8 chemicals. See Table 5 for specific limits.

  • Dangerous Goods cabinets containing chemicals must be separated by a minimum distance of 250 mm of clear air space.

  • For any Dangerous Goods cabinet containing PG I chemicals, the whole contents of that cabinet must be considered as PG I.

Table 5 – Aggregate maximum quantities (L or kg) of classes of chemicals to be stored in a location to meet the requirements of minor storage for AS2243.10.

 

  • The store floor must be made of non-absorbent, non-combustible materials which are as resistant as practicable to the chemicals stored.

  • The store must contain a spill catchment mechanism (e.g., bunding of containers or a floor pit) which is sufficiently impervious to retain the spillage until clean-up measures can be taken. Where bunding under the chemical containers is used, the capacity must be at least equal to the volume of the largest container stored in the bunded area.

  • Where incompatible chemicals are stored in the same area, the spill catchment system must prevent these substances from coming into contact with one another in the event of a spill (e.g., separate bunding containers or pits for each incompatible class).

  • Similar to laboratories, the store’s ventilation must be suitable to ensure any flammable vapours do not exceed 5% of the applicable lower explosive limit (LEL) and any toxic vapours must not exceed the relevant exposure standard. The needs of the ventilation system may differ depending on the volatile nature and quantity of chemicals stored, but the store must be designed with the principles of Section 4.5 of AS/NZS 1940, including:

    • A preference for mechanical ventilation over natural ventilation.

    • Where stores are mechanically ventilated, the ventilation system must be exclusive to the room. There must be no recirculation of exhaust air, except for a cool room where a risk assessment has been conducted and control measures put in place to prevent the build-up of a hazardous atmosphere. The system must be designed such that it is at least operational whenever a person is occupying the store, if not continuously operational, and be fitted with an airflow failure warning device.

    • Further specifications, such as the location of vents/ducting and exhausting velocities is provided in AS 1940.

  • If the store has been designated a hazardous area (e.g., potential to form an explosive atmosphere due to flammable gases, vapours, particles, etc.), it must not contain any ignition sources. See the Managing Hazardous Areas Technical Guide for more information.

  • The store must:

    • Have an automatic fire extinguishing system which is compatible with the chemicals being stored, or

    • Be equipped with an alarm which will activate when the concentration of flammable or toxic vapour exceeds set limits, when there is smoke, or when heat is generated.

Where a sprinkler-based fire suppression system (water or foam) is installed, there must be a mechanism to contain the effluent of 20 minutes of operation within the building (but not necessarily within the store itself).

  • The store must have at least one fire extinguisher compatible with the chemicals being stored immediately outside the door to the store, with a minimum size equivalent to a 2A 60B(E) for powder-type extinguishers or a 2A 20B for foam extinguishers. Additional fire extinguishers should be considered for larger stores.

  • PPE appropriate for the chemicals stored must be available at or just inside the door of the storage area (e.g., gloves, safety glasses, lab coats).

8.3.2    Chemical stores meeting AS3833 minor storage

In addition to the AS 2243.10 requirements for minor storage (section 3.5 and 3.6.1 to 2):

  • The aggregate maximum quantities of chemicals held in the store must not exceed those listed in Table 6per 500 m2 floor or ground space.

  • The store is separated from other minor stores by at least 10 m.

  • The transfer of dangerous goods from the store to the point of use must be carried out in a manner that minimizes the possibility of spillage or fire.

  • A fire extinguisher of suitable type must be installed in each minor store, located so that it is immediately accessible in an emergency along an exit route.

  • PPE such as gloves, safety glasses and lab coats must be available at or just inside the door of the storage area.

Additionally, for an outdoor store:

  • the ground around the store must be kept clear of combustible vegetation or refuse to a distance ≥ 3 m.

  • the store must be separated by at least 3 m from:

    • Any building that is not another minor chemical store, laboratory or workshop (e.g. offices, cafeterias)

    • Any place accessible to the general public where people are likely to congregate (e.g. public lawn areas, emergency evacuation points)

    • Any environmentally sensitive areas

    • A ship at permanent berthing facilities

    • The property boundary

  • The effluent or flow of a chemical spill or leak must be prevented from reaching any adjacent buildings or facilities, the property boundary or any watercourse. This may be achieved using a natural ground slope or through a diversion channel, kerb, or bund.

Table 6 – Maximum quantities (L or kg) of chemicals to be stored in a location to meet the requirements of minor storage AS3833.

 

9.0    Monitoring chemical holdings

Workers must ensure they minimise the quantities of hazardous chemicals. The storage of chemicals must be monitored to facilitate periodic stocktakes to allow for update of registers and manifest, besides proper housekeeping and prompt disposal of old/expired, contaminated and decayed chemical stocks. Refer to points 3.3.3, 3.3.4 and 3.3.5 within this guideline, the Chemicals of Security Concern Procedure, and others Occupational Hygiene and Chemical Safety Procedures and Guidelines.

9.1    Chemical registers

An up-to-date chemical register must be maintained for all the hazardous chemicals used in the workplace and be accessible to workers and emergency services. See the Chemical Manifest Procedure and the Placarding of Chemical Storage Areas for further information.

9.2    Disposal

Some hazardous chemicals may provide an expiry date on the label and SDS. Where a chemical has passed its expiry date it should not be used but be disposed according to the Environmental Management System procedures.

Old/expired, unwanted, contaminated and decayed chemical stocks can be disposed as per Chemical Waste Operating Procedure through the UQ Science Store.

9.3    Chemical waste storage

The storage of chemical waste must follow the same procedures for safe and complaint storage as per the original chemical holdings.

10.0    Training

Supervisors and Managers must ensure that UQ workers are aware or are made aware, by providing adequate information, training and supervision of the health hazards that the use, handling and storage of chemicals may present and be given induction and training (including refresher training) prior to using chemicals. Workers that access chemical storage areas must have received training in identifying chemical hazards, assessing risks associated with chemicals and be familiar with appropriate control measures. This includes how to accomplish safe and compliant storage of chemicals.

UQ has online training available, eLearning: Chemical Safety, which is mandate for completion by all UQ workers chemical users.

11.0    Emergency response

The local area must consider the nature and quantity of chemicals stored to inform the appropriate emergency response, especially the plan, for any incident occurring with the stored chemicals. Workers must know how to respond to incidents that occur while storing or during storage of the chemicals, e.g., fire, breakages, spills, unwanted reactions, exposures, etc. Workers must have access to the relevant training and spill kits for the appropriate response, including access to first aid facilities, supplies, and first aid training response. Please also refer to the Chemical Spill Response Procedure and Guideline, the Fire Safety Management Procedure, and the Placarding of Chemical Storage Areas

12.0    Incident reporting

Incidents involving chemicals during storage or while in storage (e.g., breakages, spills, unwanted reactions, exposures, etc.) must be reported by completing an incident report in UQSafe especially important is the reporting of major chemical spills and/or those that involve personnel. Incidents, including near misses, must be reported so learnings and improvements on the safe storage for chemicals can be achieved.

13.0    Monitoring, Review and Assurance

Health, Safety and Wellness Division will review this guideline, as required, to ensure its accuracy and relevance.

Organisational Units and supervisors should review chemical holdings and chemical storage on a regular basis, following incidents and near misses, when reviewing and updating risk assessments and after changes to processes or procedures.

14.0    Appendix

14.1    Relevant standards

  • AS/NZ 2243.10 Safety in Laboratories: Storage of Chemicals

  • AS 1940 The storage and handling of flammable and combustible liquids

  • AS 2714 The storage and handling of organic peroxides

  • AS 3780 The storage and handling of corrosive substances

  • AS 4326 The storage and handling of oxidizing agents

  • AS 4452 The storage and handling of toxic substances

  • AS 4681 The storage and handling of Class 9 (miscellaneous) dangerous goods and articles

  • AS 5026 The storage and handling of Class 4 dangerous goods

  • AS4332 The Storage and Handling of Gases in Cylinders

14.2    Definitions

Bunding – the use of a barrier, pit or secondary containment to prevent the spread of a chemical spill or leak.

Dangerous Goods – are chemicals assigned to a Dangerous Goods (DG) class under the Australian Dangerous Goods code. A chemical’s DG class is listed in section 14 of the SDS.

Hazardous chemicals – are any substance, mixture or article that can pose a health or
physical hazard to humans. They may be solids, liquids or gases. They satisfy the criteria of one or more hazard classes in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS), as modified by Schedule 6 of the WHS Regulation.

Most substances, mixtures, and articles that are dangerous goods under the Australian Code for the Transport of Dangerous Goods by Road and Rail (ADG Code) are hazardous chemicals, except those that have only radioactive hazards (class 7 dangerous goods), infectious substances (division 6.2) and most class 9 (miscellaneous) dangerous goods.

Incompatible – Substances which, when brought in contact with one another, may react or combine in a manner that could increase the hazard of an individual substance, for example, by causing a fire, explosion, violent reaction, liberating flammable or poisonous gases; could cause the deterioration of the container or substance; could otherwise cause injury to people or endanger property.

This definition also includes substances which are declared by a relevant regulatory authority to be incompatible.

Ignition source – A source of energy sufficient to ignite a flammable or explosive atmosphere. It may include naked flames, hot surfaces, exposed incandescent material, electrical arcs, hot particles, electrical discharge including from static electricity, chemical reactions, high intensity electromagnetic radiation including visible light or ultraviolet radiation, mechanical sparks, fixed and portable electrical equipment, portable tools or vehicles such as forklifts.

Laboratory – is any building or part of a building used or intended to be used for scientific and related work, including research, quality control, testing, teaching or analysis. This may include workshops, sheds or other areas where chemical containers are opened or handled.

Packing Group (PG) – An assigned measure of Dangerous Goods’ hazard rating. For Dangerous Goods in Classes 3, 4, 5, 6.1, 8, or 9:

Class 1, 2 and 6.2 chemicals do not use Packing Group assignations. For Class 7 chemicals, the Packing Group order is reversed.

Quenching – to terminate a reaction, to deactivate any unreacted reagents, or to destroy remaining reagents. It is a term used to describe the introduction of a material that combines with any unused reactants and effectively stops a reaction.

Safety Data Sheet (SDS) – document containing information on the health, safety and environmental aspects of a material or chemical for the purposes of storing, using and disposing of the substance in a safe way.

Segregation – Keeping incompatible goods apart from one another in one room, using a barrier or an intervening space.

UQSafe – UQ online system for recording risk assessments, injuries/illness, near miss and hazard reporting and certifications.

UQ workers – for the purposes of this procedure includes:

  • staff - continuing, fixed-term, research (contingent funded) and casual staff;

  • contractors, subcontractors and consultants;

  • visiting academics and researchers;

  • affiliates - academic title-holders, visiting academics, emeritus professors, adjunct and honorary title‑holders, industry fellows and conjoint appointments;

  • higher degree by research students; and

  • volunteers and students undertaking work experience.

Custodians
Director, Health, Safety and Wellness Mr Jim Carmichael
Custodians
Director, Health, Safety and Wellness Mr Jim Carmichael