Before working with chemicals you have to seek information about the substance's possible dangerous attributes. For instance, information about flammable, toxicity, etching, or long-term effects. Look at the label and the instruction manual. Please refer to the KIROS-database collection of workplace/supplier instruction manuals.

Handling of chemicals

  • Avoid contact with chemicals in all situations where chemicals are handled as follows: weigh, pour, normal laboratory work, transportation, cleanup, and removal of waste.
  • Avoid getting chemicals and solvent on your skin and in the eyes, work with gloves, cloth, and safety glasses.
  • Avoid inhalation of chemicals and steam, and always work using fume cupboard/hood.
  • Weighing of chemicals must always be done within the fume cupboard/hood or under spot suction. 
  • If something is spilled, clean up - observing the safety rules!

Storage of chemicals

  • Chemicals have to be stored in closed boxes with obvious labeling:
    • Substance name and for instance formula, smp./kp.
    • For instance dangerous attribute: Explosive, flammable, self ignite, water-/air sensitive, etching, toxic, allergy evoke, cancer evoke. 
  • Solvents in ether and other easy transient solvents may only be stored in refrigerator when it is explosive secured. chalice glasses may not be used. Only use plugged bottles. Covering with watch crystal for instance is not sufficient.      
  • Only small amount of flammable chemicals/solvent is allowed in the laboratory.
  • Flammable solvents in amount over 2 L may not be stored in glass vessels. 

Transportation of chemicals

  • Transportation of chemicals outside the laboratory must always be done in closed vessels. Transportation of vessels in glass must always be done in a transportation basket or wagon.   
  • Particularly transportation of volatile, smoking, corrosive, flammable, and explosive chemicals and substances may not take place in a elevator with people. For instance solvents, brom, chlor, floating nitrogen, carbonic acid ice and smoking acid.  

Chemical spillage

  • Spilt chemicals must be collected immediately. Liquids are to be absorbed in porous material (sand, diatomaceous earth, mica, vermiculite etc.), maybe first after neutralization and/or dilution with water. Spilled powder may raise dust when collected. Therefore use personal protection. Disposal of garbage: see section chemical waste.
  • Clothing hit by chemical waste must be removed as quick as possible. Especially shoes, watch straps and the like which have absorbed liquid, must be removed immediately.

Peroxid formation and other unstable substance

For substances or packaging materials with possible explosive attributes age, storage temperature, light influence and air influence can be final of the stability and it is particularly important that these substance are not purchased and stocked in larger quantities.

The Danish Emergency Management Agency has careful information about both peroxid formation and formic acid. Be careful already by transportation and opening of bottles if suspected of high peroxid content.
Peroxide formation classify in 3 groups (A, B and C). A simple way to inspect of peroxids in for instance ether is by mix a couple of ether mL with a potassiumiodide solution and a couple of drops attenuate hydrochloric acid and shake the mix. If the color turn brown it indicate a certain peroxid content.  

The peroxid content can be controlled by peroxid strips (Merck 1.10081.0001, level 1-100 mg/l H2O2) and/or titanium(IV)oxysulfat-reagens (Fluka 34244). These methods often show different results. The recorded values will often be lower when measured with sticks than with titanoxysulphate method and too triacetoneperoxid is the difference high. Test should always makes before heating, concentration, and disposal.   
Most peroxide formation chemicals is when delivery added inhibitors and chemical organisations guarantees normal a durability in unopened packaging of 3-5 years from production date. Too chemicals which is not added inhibitors is the durability shorter.
Some peroxide formation can cause explosive peroxide levels without concentration of the solvent and the general guideline to substitution involves for instance specific reasons to use diisopropylether.

If you suspect or find an actual high peroxide content (suggested limit at 100 ppm), contact your work environment leader for further steps. This can as among others be destruction of peroxides with a acidic solution of ferrosulphate.
Packaging with unstable chemicals have to be marked with label. At the label make a note of date of purchase and opening, stability control, placement and other things.

Suggestion to marking of labels of unstable substance:
Purchase / initials
Opening date / initials
Stability control test / initials
Locality / initials / department name

Pressure bottles, floating nitrogen, carbonic acid ice (dry ice)

Pressure bottles with compress volatile is often used by all forms of laboratory work and cause more than one risk factor. Damaging of pressure bottles can cause explosions as a consequence of high pressure. A broken valve can cause heavy volatile leakage and the bottles behave as a projectile. The leakage volatile from a damaged bottle or a bad complete experiment can cause explosion and fire or poisoning, cauterisation or strangling after the volatiles nature. A overview over the normal used compress volatiles follows:   

The pressure by 20 oC in trade vessels is stated.

150 -200 atm 10 - 60 atm 1 - 10 atm
Hydrogen Carbon dioxide            (56 atm) Ammoniac                 (8.5 atm)
Oxygen Chlor hydrogen            (42 atm) Chlor                       (6.5 atm)
Nitrogen Acetylen i acetone       (20 atm) Methylenchlorid         (8.5 atm)
Helium Sulphur hydrogen         (18 atm) Sulphur dioxide          (3.2 atm)    
Bortriflourid Methylbromid            (1.9 atm)
Ethyl Fluoride hydrogen       (1 atm)

Work with and storage of floating nitrogen and carbonic acid ice (dry ice) involves risk of frostbite (N2, -196 oC ; CO2, -78 oC) and of nitrogen accidents (1 L floating carbonic acid will by 20 oC and 1 atm volume about ¾  m3). Carbon dioxide also has physiological effect and can in concentration of 10-20 % cause immediate dead. Floating carbon acid is often used in cold traps and can cause condensation of atmospheric oxygen in the trap as well as in the floating nitrogen in the dewar vessel. This oxygen can cause heavy explosions in presence of oxides substance. For instance organic connections. Therefore after use you have to take the coldtrap up from the dewar vessel and close the vacuum. The tap to the coldtrap has to remain open because these substances there for instance are condensed can get out.    

  • Transportation of pressure bottles always have to by on a transport vehicle.
  • Transportation of pressure bottles may not take place with pressure reducing valve attach. Transport always with security cap attached.  
  • Both empty and full pressure bottles have to be secured against tipping both where they are used and stored.
  • Pressure bottles may not be exposed to knock or strong heating (sun or heating instrument). Especially one-sided heating.
  • Pressure bottles may not be opened with weaker tools than prescribed.  
  • Pressure bottles may not be emptied completely. For instance chlorine bottles under 2 atm.
  • Pressure bottles have to be protected against backsuction from wash bottles and reaction vessels by help of an interject security bottle.  
  • There have to be a triangle sign everywhere pressure bottles are used or stored. Pressure bottles are to be removed in case of fire.
  • When drawing and decantration of floating nitrogen, protection glasses or face shade have to be used. Dewar-vessel can explode with surprising intensity.
  • Transportation of floating nitrogen and carbonic acid ice (dry ice) may not take place in manned lifts because of suffocation danger. Therefore neither transportation in closed vehicles.     
  • First aid by frostbite and suffocation accidents: See first aid.
  • Do not pump atmospheric air through a cold trap which being cool down with floating nitrogen (condensation of oxygen inside the trap cause risk of explosion).