Dangerous Goods (DG) Class 4.1 flammable solids, such as magnesium ribbon, should be stored in a secure, non-combustible container in a locked chemical storeroom, segregated from incompatible substances.
Class 4.1 dangerous goods are compatible with other Class 4.1 substances, but are not likely to be compatible with Class 3 flammable liquidsi.
Sulfur and naphthalene, also dangerous goods Class 4.1, are compatible for storage with magnesium ribbon. Iron filings are classed as a non-hazardous and a non-dangerous good. However, storage with dangerous goods Class 4.1 is appropriate as the substance is liable to spontaneously heat and ignite under favouring conditions.
AS 2243.10 Safety in Laboratories:ii
4.7.2 Class 3 dangerous goods (flammable liquids) and combustible liquids states:
A chemical storage cabinet or cupboard used to store these liquids shall not be used for the storing of dangerous goods of any other Class.
4.7.3 Class 4.1 dangerous goods (flammable solids) states:
A chemical storage cabinet or cupboard used to store Class 4.1 dangerous goods shall not be used for storing dangerous goods of any other Class.
Science ASSIST will be developing more specific guidelines for labelling and storage in the coming months for chemicals included in our List of recommended chemicals for science in Australian schools.
Science ASSIST recommends that all chemical storage areas be locked, with access restricted to authorised members of staff only. See our information sheet on AIS: School science area security.
Class 4 Dangerous Goods:
There are a number of key considerations for controlling the fire risks from storing and handling Class 4 dangerous goods. These include:
- ensuring non-combustible materials are used in the construction of buildings and storage areas;
- installing and maintaining appropriate fire protection systems;
- utilising separation distances (or barriers such as fire resistant screen walls);
- ensuring ignition and heating sources are controlled within the storage and handling areas, for example, electrical equipment used in these areas must be intrinsically safe;
- ensuring adequate ventilation and/or extraction is provided to avoid creation of a hazardous atmosphere or hazardous area;
- ensuring that the storage area is moisture free and protected from the elements;
- ensuring that measures are taken to protect light or temperature sensitive materials (e.g. by installing temperature controls or protecting from direct sunlight).i
Class 3 Dangerous Goods:
Flammable solvents (dangerous goods class 3) must be stored in an Australian standard approved flammable solvents cabinet.
Magnesium (magnesium ribbon and magnesium sheet) (CAS number 7439-95-4) is listed as a drug precursor, category 2. This chemical may only be available for purchase by account customers and a Permit/Licence/End User Declaration may be requirediii, iv . Storage should be in a locked area, and only minimum quantities made available for practical activities. Teachers should dispense a small amount of the product to students.
General Considerations for Chemical Storage of Magnesium:
When planning or restocking a chemical store, a risk assessment should be conducted in conjunction with a current Safety Data Sheet (SDS) to check for the DG class, subsidiary class, packing group (PG) and advice on compatibility with other chemicals.
Wherever possible, dangerous goods and hazardous substances must be stored in original containers and labelled appropriately in accordance with legislation.
Chemicals must be stored in their respective classes, taking into account incompatibilities within and between classes.
Strategies such as the use of separation distances i, impervious physical barriers or storage in separate areas should be used to prevent contact between incompatible dangerous goods classes.
Proper storage and use of flammable or combustible dangerous goods is absolutely critical in maintaining a safe work place. All ignition sources should be eliminated or controlled. Ignition sources include heat (e.g. direct sunlight), naked flames, and electrical fittings (sparks or static discharge). Solvent vapours are heavier than air. These can pool in low-lying areas and travel significant distances to an ignition source.v
Suitable ventilation to prevent the build up of hazardous vapours, gases or fumes should be in place.
Controls should be in place to prevent unauthorised access to the chemical store.
i ‘Managing incompatible goods. Segregation tool’, Worksafe Queensland website https://www.worksafe.qld.gov.au/injury-prevention-safety/hazardous-chemicals/managing-incompatible-goods/segregation-tool (23rd July 2015)
ii These extracts from AS/NZS 2243.6 2010 Safety in laboratories – Part 10: Storage of Chemicals are reproduced with permission from SAI Global Ltd under License 1407-c117.
iii ‘Code of Practice for supply diversion into illicit drug manufacture’, The Plastics and Chemical Industries Association website, http://chemistryaustralia.org.au/ (Accessed October 2015)
iv Science ASSIST 2015. List of recommended chemicals for science in Australian schools. Science ASSIST website http://assist.asta.edu.au/resource/3052/list-recommended-chemicals-science-australian-schools (Accessed October 2015)
v ‘Flammable’, The MSDS Hyperglossary. Interactive Learning Paradigms Inc. website, http://www.ilpi.com/msds/ref/flammable.html (Accessed October 2015)
‘Class 4 – Flammable solids’, Australasian Institute of Dangerous Goods Consultants website, https://web.archive.org/web/20170526223540/http://aidgc.org.au:80/class-... (Original website no longer available, this copy made available through the Internet Archive, December 2017)
Safe Work Australia 2012. Managing Risks of Hazardous Chemicals in the Workplace. Code of Practice. July 2012. Safe Work Australia website http://www.safeworkaustralia.gov.au/sites/SWA/about/Publications/Documen...
University of NSW 2014. HS404 Dangerous Goods Storage Guideline. Version 1.3, April 2014. https://www.gs.unsw.edu.au/policy/documents/HS404.pdf
Worksafe Queensland 2013. Managing risks of hazardous chemicals in the workplace. Code of Practice 2013, Worksafe Queensland website. https://www.worksafe.qld.gov.au/__data/assets/pdf_file/0005/58172/Managi... (Updated May 2017).
Worksafe Victoria. 2013. Code of practice for the storage and handling of dangerous goods. Worksafe Victoria website http://www.worksafe.vic.gov.au/__data/assets/pdf_file/0005/118436/Code-o...