School of Chemistry School of Chemistry

6. Appendices

Section Contents

  1. Safety audit checklist
  2. Risk Assessment
  3. Risk Assessment Form
  4. Safe operating procedures for glass vacuum lines
  5. Ultraviolet lamp safety requirements
  6. Generic Assessment for Laboratory Activities to cover DSEAR 2002

6.1 Safety Audit Checklist

The checklist used for auditing can be downloaded, for reference, as either the Word document or the Acrobat .pdf file.

6.2 Risk Assessment

Set out below is a proposal for amending risk assessments to diminish the use of generic assessments and restrict them only to genuinely "generic" operations. The intention of this change is to force people to consider the implications of their actions, the suitability of the equipment and the interaction between components. It is believed that there are simply too many instances where people hide behind wide ranging generic assessments without proper consideration of the consequences of scale, interaction or alteration in the character of components. The continuation of this approach on a regular basis carries potentially serious consequences.

Risk Assessment Flow Chart

Printing this chart

If you would like to print out the risk assessment chart, you can download the Acrobat .pdf file (you must have Adobe Acrobat Reader installed for this option).

6.3 Risk Assessment Form

Risk Assessment Forms can be downloaded for printing as either the Word document or the Acrobat .pdf file (you must have Adobe Acrobat Reader installed for this option).

6.4 Safe Operating Procedures for Glass Vacuum Lines

Before operating vacuum pumps, carry out visual inspection of glassware to check for cracks and check that all stopcocks are free to open and close. Glassware which is regularly subjected to temperature extremes or which is liable to experience mechanical stress in cleaning operations should be routinely checked by the glassblower for strain.

Glass Dewer vessels should be contained in metal or plastic vessels.

Glass bulbs with a volume greater than 100 cm3 should be taped or encased in a metal mesh.

Any vessel which is cooled in liquid nitrogen should NOT be allowed to warm up without first being evacuated to a pressure of less than 1 mm Hg in order to ensure that no liquid air has been condensed.

Carry out risk assessment of work to be undertaken.

Check that all Personal Protective Equipment (PPE) required by the risk assessment is available, e.g.

Low risk: safety glasses, lab coat.
High risk: full face visor, gloves, lab coat and any safety screen.

INFORM OTHER WORKERS IN THE LABORATORY OF THE RISKS ASSOCIATED WITH THE PROCEDURE.

Printing these instructions

If you would like to print out these instructions, you can download the Acrobat .pdf file (you must have Adobe Acrobat Reader installed for this option).

6.5 Ultraviolet Lamp Safety Requirements

  • Principal Investigators (PIs) must ensure that individuals who will be using UV lamps under their supervision are adequately trained in the safe methods of using the equipment and are aware of the hazards associated with these lamps. Undergraduate students must be supervised by a competent member of staff.
  • Operators of UV lamps must make sure that they are wearing UV filtering face shields or eye protection depending on type of lamp used. Gloves should also be considered if prolonged exposure to the hands is expected.
  • Any fitted safety screen must always be correctly used when the lamp is being operated. This is as well as, and not instead of, the eye protection required.

Hazards associated with Ultraviolet Lamps

  • Damage to skin caused by exposure to UV radiation. Repeated overexposure of skin to UV has been linked with premature aging, wrinkles, and most seriously, skin cancer.
  • Eye damage can result in corneal scarring and cataract formation.
  • Burns caused by contact with a hot UV lamp.
  • Fire ignited by hot UV lamp
  • Interaction of other chemicals with UV radiation.
  • Damage caused to apparatus placed close to UV lamp.

Printing these instructions

If you would like to print out these instructions, you can download the Acrobat .pdf file (you must have Adobe Acrobat Reader installed for this option).

6.6 Generic Assessment for Laboratory Activities to cover DSEAR 2002

Flammable liquids are defined in accordance with the Chemical (Hazard Information and Packaging for Supply (CHIPS)) Regulations as a substance, mixture or preparation with a flash point equal to or less than 55° C. Highly Flammable liquids are those with flash points below 21° C and Extremely Flammable liquids have flash points below 0° C and a boiling point equal to or less than 35° C

Liquid dangerous substances include petroleum spirit and derivatives thereof, many aliphatic hydrocarbons and derivatives. Examples include acetone, benzene, carbon disulphide, diethyl (and other) ethers, ethanol, ethylacetate hexane petroleum ethers and toluene.

Risk Factors

Factors which promote an increase in the likelihood or severity of fire (or explosion) include the following.

  • The use of a flammable liquid under conditions which allow the formation of a flammable (explosive) vapour-air mixture;
  • The use of a Flammable liquid with a flash point below ambient temperature or at a temperature above its flash point;
  • The use of a flammable liquid in open vessels or apparatus;
  • The use of flammable liquids in proximity to ignition sources such as flames, electrical equipment or hot surfaces;
  • The use of flammable liquids in unventilated or poorly ventilated areas;
  • The use of any flammable liquid as an aerosol;
  • The use of a flammable liquid in combination with an oxidizing agent or other incompatible substance;
  • Dispensing or decanting a flammable liquid;
  • The use of large volumes of flammable liquid.

Risk Control Measures

Controlling, including the avoidance, reduction, and mitigation of the harmful effects of flammable liquids include the following.

  • Do not use a flammable liquid if a non-flammable liquid is available and appropriate;
  • If a flammable liquid must be used choose one with the highest flash point and/or boiling point
  • Use the least amount of flammable liquid consistent with the laboratory activity;
  • Contain the flammable liquid in apparatus or equipment that prevents uncontrolled release, vaporization or spillage.
  • Prevent the formation and accumulation of flammable (explosive) atmospheres by natural or mechanical dilution ventilation sufficient to dilute vapour-air mixtures to less than 25% of the lower flammable (explosive) limit;
  • Whenever practicable handle flammable liquids in a fume cupboard or other local exhaust ventilation device to remove vapour from the laboratory.
  • Use flammable liquids at the lowest possible temperature consistent with the laboratory activity;
  • Whenever practical use inerting or purging techniques to remove oxidant and so prevent the formation of explosive atmospheres;
  • Provide bund or spillage protection for containers or apparatus;
  • Identify and remove all ignition sources by distance from potential explosive atmospheres;
  • Where ignition sources cannot be avoided or made safe by distance or barriers use suitable equipment according to hazard zone classification;
  • Areas where an explosive atmosphere may be formed under normal laboratory operating conditions should be marked "Ex" and all equipment in that area rated appropriately;
  • Keep receptacles and containers securely closed immediately after use and return container to appropriate storage area;
  • Carry or transport only sealed or closed containers in a suitable carrier so they cannot be dropped or strike against one another;
  • Use appropriate dispensing devices to transfer flammable liquids from large to small containers and provide spill trays and suitable inert absorbent;
  • Do not permit the uncontrolled mixing of compressed air, oxygen or oxidizing agents with flammable liquid unless adequate safety measures are in place to control or limit the rate of mixing and the resulting chemical reaction;
  • Do not permit the wearing of synthetic laboratory clothing where there is a potential to form an explosive atmosphere;
  • Do not keep flammable liquid residue or waste in the laboratory unless in a suitable closed container;
  • Keep flammable liquid containers of capacity greater than 500 cm3 in a closed non-combustible and fire-resisting bin or cupboard;
  • Do not store flammable liquid and waste in proximity to the entrance / exit of the laboratory;
  • Provide suitable fire extinguishers (dry powder, AFFF foam or carbon dioxide) in each laboratory and adjacent to each flammable store;
  • Inform, instruct and train all laboratory workers and others in appropriate emergency procedures to deal with spills or vapour release and in the event of a fire or explosion.

Persons at Special Risk

Persons working with extremely flammable liquid (carbon disulphide, peroxidisable ethers), those working with flammable liquids in combination with oxygen, or other oxidizing agents, pyrophoric materials or materials reacting violently with air or water.

Exclusions

This model assessment may not be adequate for the following laboratory activities:

  • Work in which flammable liquids are used with oxidizing agents, spontaneously combustible substances or those which ignite on exposure to water;
  • The use of flammable liquids in apparatus of capacity greater than 5 litres.
  • The use of flammable liquids in a pressure vessel or system where the product of the pressure and volume exceed 200 bar litres.

In This Section