SOP for Laboratory Safety

Standard Operating Procedure for Laboratory Safety

Standard Operating Procedure for Laboratory Safety

1.0 Purpose:

 To lay down a procedure for Safety in Laboratory.

2.0 Scope:

The scope of this procedure is applicable for ensuring Safety in the Laboratory.

3.0 Responsibility:

QC Personnel: Strictly adherence to the standard operating procedure for laboratory safety.

4.0 Definitions:


5.0 Procedure:

5.1 A chemical laboratory is a place associated with hazardous and poisonous chemicals and reagents, so all QC personnel should work with alertness and take certain precautions.

5.2 A senior person is assigned as the in-charge of a chemical laboratory, irrespective of the nature of the work to be done there.

5.3 Each and every person in the laboratory should work carefully and safely.

5.4 Those working in the laboratory should always pay attention to what is going on around them and be aware of the possible dangers arising from the work of others as well as from their own experiments.

5.5 Refer to MSDS while handling hazardous reagents or solvents.

5.6 Handle all hazardous or poisonous chemicals very carefully.

5.7 Use Personal Protective Equipment (PPE) such as hand gloves, safety goggles, nose masks, and safety shoes, whichever is applicable and wherever necessary.

5.8 Conduct in the laboratory should be safe and responsible.

  • Except in an emergency, running or any over hurried activity, is forbidden. Jokes and other irresponsible activities are not allowed.
  • Do not Eat, Drink or Smoke at the work area and do not store eatables in the refrigerator used for storing chemicals, microbial cultures and bacteriological media as these constitute a further avoidable, risk of ingestion of toxic substances and in case of smoking an obvious fire hazard.
  • One must adopt a thoughtful, careful and methodical approach to what one is doing. In particular, concentration on the job in hand and not allowing the attention to be distracted is recommended and unnecessary distraction to the others is deplored.
  • Do not leave experiments, which needed constant attention, for eg. Boiling of organic solvents and hazardous / poisonous chemicals / reagents.
  • Inform the House – Keeping boy of the possible dangers arising out of the handling of any chemicals remaining in the glassware being taken for washing.
  • All the laboratory persons are prohibited from carrying unauthorized experiments.
  • Do not use mouth suction for filling of pipettes irrespective of the solvent involved.

5.9 Housekeeping and Tidiness:

  • Always keep the surrounding working area clean and tidy, as this will encourage you to work in methodical and orderly manner.
  • Ensure that all the passageways, Exits, Fire Fighting Equipment and other Emergency Aids like First Aid Kit are kept free from obstructions such as Boxes and Bottles.
  • Any liquid spilled on the floor should be mopped up with due consideration to necessary precautions.
  • Spilled acids must be contained, absorbed by absorbing pads. Collect the contaminated pads in poly bag & stick label as “Hazardous Waste”. Then moping of the area by water / disinfectant solution.
  • Oil must be covered with sawdust before sweeping up.
  • Ensure that the splinters of broken glassware are removed properly and placed in dedicated bins.
  • All the equipment and reagents should be returned to their proper places after use and not left to clutter up the bench.

5.10       Emergency procedure:

  • Every employee working in the laboratory should ensure the location of all the Exits and Fire Escapes, which is easy to access.
  • All the employee should also know the location of Fire Fighting Devices and make sure that they know basic concept of firefighting devices about how to operate. Proper authorities should carry out the checking of such devices at a regular intervals and this process shall be documented.
  • All the employee should be familiar with the location of the First Aid Kit and the position of the nearest intercom that in use.
  • Emergency dial number and the contact numbers of key persons & EHS Head / In charge should be displayed in all prominent places

5.11 After working hours:

  • No one should ever work alone in the laboratory after normal laboratory working hours.
  • Experiments that need to run in the absence of the chemist, concerned shall be labelled “Don’t Disturb” and “Please Leave On”. Label should stick on experiment, which is to be left for running after Normal Laboratory Working Hours.
  • If the experiment is to be continued overnight, the apparatus should be labelled clearly as to the nature of the reaction and the likely hazards. Clear instruction should be left so that an unqualified person can terminate the experiment in urgency.

5.12 Storage of chemicals in the laboratory area:

  • All the surplus chemicals or chemicals which are seldom used should be stored in a separate area which is isolated from source of fire and electric sparks and which is provided with sufficient fire fighting equipment.
  • Incompatible chemicals should be separated from one another.
  • Heavy containers and bottles of dangerous chemicals should be returned as soon as possible to the main chemical store.
  • Any winchester bottle, whether containing dangerous or innocuous material, needs to be carried a short distance, should be supported at the base and at the neck – never at only one of these points.
  • Fume cupboards must be kept free from surplus chemicals and discarded apparatus.
  • Char summarizing the meaning of the hazard symbols should be displayed prominently in the critical areas and when the chemicals are transferred to another container the same hazard code should be placed on the new container.
  • In case of bottles, which have lost their labels, the contents should be positively identified and re-labeled. If any doubt the material should be disposed off safely.

5.13 Handling of apparatus:

  • Apparatus must be well placed away from the edge of the laboratory bench to avoid risk of falling on the floor.
  • Broken glass tubing and rods :
    • Glass tubing should be cut with care. Nick the tube with a Glass Knife or a small ampoule file, and hold it in a piece of cloth or with hand gloves before snapping a motion, which should be executed away from the face. The cut end of the tubes should be flame rounded and preferably lubricated with silicon before further use.
    • When assembling apparatus, Ground Glass Joints are preferable because they obviate the risk of boring and fitting corks. If corks are used as a cork borer slightly larger than the tube or rod should be used to bore holes in rubber bungs to ensure a good fit.
    • Use a sharp cork borer and lubricate with suitable glass lubricants, when boring holes in corks. Roll the cork to compress it and use a borer equal in size to the tube or rod. The cork borer should be directed downwards on to a wooden plank and not towards the palm of hand.
    • Removal of glass tubing from Corks and Bungs: When removal, cut and split the bung away, where this is convenient. Alternatively, loose by sliding a well-lubricated cork borer of suitable size along the tube and gently twisting it through the bung.
    • Chipped or Jagged Glassware: Examine all apparatus for defects before any experiment. Do not use badly shipped or cracked glassware.
    • Pipettes: When Pipetting corrosive or poisonous liquids an aspirator bulb must be used and not mouth suction. This applies particularly to dilute alkalis. Pipetting of hot solutions and volatile liquids is dangerous because developing pressures may expel liquids from the tip of the pipette.
    • Removal of tight glass stoppers: Tap alternatively at each side of the stopper with a piece of wood, holding the thumb hard against the opposite side of the stopper. If this is unsuccessful and the contents of the bottle are not dangerous, toxic or highly inflammable gently warm the neck of the bottle. If this fails mark round the neck with glasscutter and place a red-hot glass rod on the neck to cause break round the mark. Carefully transfer the contents of the bottle to a new container.
  • Handling of dangerous materials : All the chemicals should be regarded as potentially dangerous, although actual danger generally arises out of misuses. In general chemicals should not be handled with bare hands.
  • Selected list of Highly Toxic Materials : The chemicals listed here are some of the commonly used Laboratory Chemicals having high degree of toxicity. The values indicated in the parenthesis indicate the recommended limit in ppm as adopted by Health and safety executive UK.

Aniline (2),

Hydrogen Sulphide,

Acetic anhydride                      


Arsenic compounds                  









Picric Acid


Hydrochloric Acid 

  • Reactive inorganic reagents :
    • Strong acids :
    • All of the following chemicals react violently with bases and most give off very Harmful Vapors.
      • Hydrobromic Acid and Hydrogen Bromide
      • Hydrochloric Acid and Hydrogen Chloride
      • Hydrofluoric Acid and Hydrogen Fluoride – both react readily with glass and quickly destroy organic tissues. New thick rubber or plastic gloves should be worn after carefully checking that no holes are present on them. Skin burns must receive specialized Medical attention.
    • Nitric acid (Concentrated and Fuming)
      • Perchloric acid – This can react violently with metals (e.g. aluminium) and organic material such as clothes, wood, plastics.  In addition the fumes, which are readily evolved from liquid acid, are easily absorbed from these substances, which are thus rendered violently flammable or explosive. For this reason, Perchloric acid should not be stored / handle in a wood – framed fume cupboard or near to any organic matter.
      • Sulphuric acid – This can react violently with water. It should be mixed with water very carefully, by pouring into cold water through a thin stream to prevent acid splashes or spray. Never pour water into the acid.
      • Chlorosulphonic acid – This is highly corrosive liquid, which reacts violently with water.
    • Strong bases
      • Calcium Oxide, Potassium Hydroxide, Sodium Hydroxide – these reacts violently with acid, generate heat with water, and have a powerful corrosive effect on the skin, particularly the corneal tissue of the eye.
      • Ammonia, concentrated Hydrazine Solution – Hydrazine Vapor is harmful.
      • Sodamide – usually obtained in granular form, which reacts violently with water, it is irritant and corrosive in finely divided form.

5.14 Hazards due to toxic chemicals :

  • A very large number of compounds used in chemical laboratories are toxic. Indeed, nearly all the substances are toxic to some extent and the adoption of safe and careful working procedures, which prevent the entry of foreign substances into the body, is of paramount importance. Toxic substances can enter the body through the following routes.
  • Ingestion through the Mouth :
  • This can occur through accidental contamination of the food, drink and by misuse of mouth pipettes. Storing of eatables in the laboratory refrigerator is strongly condemnable.
  • Inhalation into the Lungs : This is common pathway for the absorption of toxic chemicals; these may in the form of Gases, Vapors or Dust. All Toxic Powders, Volatile Liquids and Gases should only be handled in efficient fume cupboard or with a mask worn round the face. The practice of sniffing the vapors of unknown compounds for identification purposes should be conducted with caution.
  • Direct Absorption through the skin to the Blood Stream : This is also a common route for the absorption of Toxic substance, whether Liquid, Solid or Gaseous. Wearing rubber or plastic gloves in addition to the usual Laboratory white coat may reduce the danger. Protective gloves are often permeable to organic solvents and are easily punctured. They should be frequently inspected and replaced, when necessary.

5.15 Fire and explosion hazards :

  • All fires however small must be reported to the supervisor and safety in charge. This is required so that safety may be amended or enlarged wherever necessary and so that fire-fighting equipment can be serviced without delay.
  • Specific methods for dealing with the more notable fire hazards are given below.

5.16 Flammable solvents :

  • Flammable solvents :
    • Particular care must be taken while handling of flammable solvents and highly volatile substances.
    • The vapor may drift to adjacent ignition source and burn back to ignite the main bulk of the liquid.
    • Never allow any vapor of the volatile liquid to escape into the open laboratory.
    • Bulk dispensing, if needed, should take place in a specially designated area.
  • Ignition source :
    • Naked flames should not be used in the laboratory.
    • Heat the reaction mixtures by means of steam bath, electric heating mantle, hot plate oil batch etc.
    • If Bunsen flames have to be used, they should be lit only after careful survey of neighbouring apparatus and chemicals revealed no fire hazards.
    • The flame should be turned out whenever it is not actually in use.
    • Do not put the gas-air Bunsen flames in bright sunlight, as the flame may be invisible.
    • Do not allow flammable vapor to accumulate in the vicinity of electrical devices such as thermostats, stirrer motors, vacuum pumps, drying ovens etc., as it may be ignited from electrical contracts.
    • Never switch on electrical bulbs or light matchsticks etc, when you feel the odor of flammable gases or vapors as enter the room.
    • Warm or damaged Cables, Sockets, Plugs are dangerous. Get them repaired. Ensure that all electrical equipment are properly earthed and open plugs are adequately closed.
  • Leaking cylinders :
    • The explosion of air hydrogen mixture is always violent. Hydrogen passes very quickly through a small leak and explosive mixture form with air (4-72 %).
    • Do not allow a cylinder containing oxygen to leak over a period when normal ventilation is tuned off, the concentration of Oxygen in air may become great enough to cause a very fierce fire in the event of ignition source present.
  • Sunlight : Ensure that inflammable materials are removed from the vicinity of flasks or bottles, as strong sunlight may be focused on to them by flasks and bottles acting as lens.
  • Spontaneous combustion : Nitrates, chlorates, chromates, peroxides etc should not be disposed off in general waste bins containing organic materials because of fire risks.

5.17 Some specific dangers of explosion :

  • Perchloric acid, chlorates and perchlorates, chromium oxide, chromates and dichromates, concentrated nitric acid and nitrates are some of the potentially dangerous mixtures.
  • Peroxides in ether solvent :
    • This one of the commonest causes of explosions in organic chemistry laboratories. Simple dialkyl ethers like diethyl ether and di-isopropyl ether and cyclic ethers like 1,4-dioxane and tetrahydrofuran form less volatile peroxides on exposure to light and air. If therefore one of these is purified by distillation the peroxide concentration in the residue is increased and a violent explosion may occur.
    • In view of the above observation such solvents like those mentioned above should not be stored for a longer period or in half-empty bottles. Containers should be of dark glass.
    • Before distilling peroxide test should be performed and if the test is positive the peroxide should be removed.
  • Chromic acid and Nitric acid as cleaning agents : Violent explosion may take place when attempts are made to remove tarry residues from reactions flask by adding chromic acid mixtures or concentrated nitric acid, and heating. If such residues are not removed by chromic acid mixtures in the cold, followed by scrubbing with scouring powder, than the only safe course is to throw the flask away.

5.18       First Aid :

  • All the employees should know the location of first aid kit. All the solutions prepared for the purpose of providing first aid should be stored in suitable containers and the containers should contain on them details like preparation date, expiry date uses and instruction to use. The following are some of the tips on first aid in normal laboratory accidents.
    • Concentrated Acids and Bases: splashes caused by these chemicals should be washed by copious amount of water followed by soap.
    • Nitric acid splashes: A 2 % solution of Sodium Hypo Chlorite is recommended for swabbing fuming Nitric Acid splashes.
    • Bromine: Skin burns due to bromine should be washed with copious amount of water and must be bathed with a dilute solution of sodium or ammonium thiosulphate.

6.0 Acceptance Criteria:

Not applicable.

7.0 Frequency:

Not applicable.

8.0 Format for recording:

Not applicable

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