Chemical storage

Many low risk chemicals, such as buffers, salts, and drying agents, can be stored in open laboratory work benches or shelving on the work benches.  However, the majority of chemicals (or dangerous goods) found in laboratories must be stored in specialized types of storage units for safe storage when not in active use. 

  • It is not good practice to store all chemicals in alphabetical order by name. 
  • Each chemical must be evaluated to determine where and how it should be stored according to chemical compatibility and manufacturers’ recommendations.
  • As a general rule, flammable or combustible liquids, toxic chemicals, explosive chemicals, oxidizing agents, corrosive chemicals, water-sensitive chemicals and compressed gases should be segregated from each other. 
  • For more details, please refer to the chemical compatibility guidelines.

General chemical storage practices

  1. Do not store liquid chemicals above shoulder height. Lips or restraints on storage shelves are recommended to prevent bottles from falling off.
  2. Label storage areas and cabinets to identify hazard classification.
  3. Ensure chemical containers have proper WHMIS labels before storage.
  4. Flammable chemicals must be stored in flammable storage cabinets or storage rooms with only small quantities available for immediate use.
  5. Storage of chemicals on the floor should be avoided. If bottles are stored on the floor they are to be contained in a form of secondary containment.
  6. Excessive chemical storage in hoods is not acceptable; this practice interferes with the airflow in the hood.
  7. Stored chemicals shall be in cool and dry areas.
  8. Chemical waste shall be placed in the appropriate waste containers and segregated.
  9. Chemicals should be dated when received and any old chemicals should be disposed of through the hazardous waste system.

Flammable storage cabinets

In each laboratory only 10 L of flammable and combustible liquid is permitted to be stored outside of a storage cabinet where only 5 L of the total amount can be a Class I liquid.  Volume of flammable or combustible liquids above 10 L must be stored in closed containers within flammable storage cabinets.    

  • Flammable storage cabinets are designed to store material meeting the flammable criteria of flashpoint less than 22.8°C and a boiling point of 37.8°C or combustible criteria of flashpoint less than 93.3°C.
  • Flammable cabinets are tested by the manufacturer to meet fire code and specific installation instructions are required to maintain conformance with the fire code.

Venting

The BC Fire Code and US National Fire Protection Agency (NFPA) recommends against venting flammable cabinets and that any vent openings must be sealed.  Venting a cabinet could compromise the ability of the cabinet to adequately protect its contents from involvement in a fire nor contain a fire that may unintentionally start within because cabinets are not fire tested with any venting. 

Vent connections are provided on flammable cabinets by manufacturers for the convenience of the purchaser if they choose to vent a cabinet.  An advantage of venting a flammable cabinet is to prevent build up of odour within the cabinet. Specific requirements must be met such as the capability of the vent to close off in case of a fire within the flammable cabinet, appropriate vent piping size and location of the vented flammable cabinet. 

  • At UVic, all flammable storage cabinets found underneath fume hoods are not vented. 
  • The majority of free standing flammable storage cabinets at UVic are not vented. 
  • A small number of free standing storage cabinets found on campus are vented, and are connected via static venting pipes which meet regulatory venting requirements; however, they are not truly effective in reducing odour build-up.
  • Odours can be reduced by improving housekeeping and placing strong odour chemicals in labelled second outer bottles.

Regulatory information

Different classes of flammable or combustible liquids from BC Fire Code (Division B, Part 4.1.2.1)

Class

Flash point

Boiling point

Flammable liquids

Class IA

below 22.8 °C

below 37.8 °C

Class IB

below 22.8 °C

at or above 37.8 °C

Class IC

at or above 22.8 °C but below 37.8°C 

 

Combustible Liquids

Class II

at or above 37.8 °C and below 60 °C

 

Class IIIA

above 60 °C

below 93.3 °C

Examples:

Class I

Class IA

Class IB

Class IC

·   Diethyl ether

·   Pentane

·   Hexanes

·   Petroleum ether

 

·   Acetone

·   Toluene

·   Ethanol

·   Isopropanol

·   Tetrahydrofuran

 

·    Styrene

·    Xylene

       

 

Class II

Class IIIA

·    Diesel fuel

·    Kerosene

·     Mineral oil

Corrosive storage cabinets

Corrosive storage cabinets are used to store corrosive material, in particular acids or bases. These cabinets are not tested to meet fire codes but are constructed of materials to resist corrosion and avoid incompatible materials that may cause generation of hazardous or flammable vapours. 

  • Bases and acids are incompatible chemicals and must never be stored together in the same corrosive storage cabinet but rather in separate cabinets dedicated to base or acid only. 
  • Where practical, keep organic and mineral acids separate within an acid cabinet using, for example, secondary containers. 

Venting

At UVic, corrosive cabinets are typically found underneath fume hoods and connected to the exhaust system to prevent build up of any acidic vapour of acid storage.