Laboratory Ventilation

Please notice that in a well-ventilated laboratory and a pressure cell, these experiments can be executed safely. In seven years of graduate research activity at the Chemical Engineering Department of the University of Akron, only one catalyst ignition and one real CO alarm occurred. Several false CO alarms were sounded until someone noticed that they always happened about 2 30 PM. As it turned out, one maintenance employee parked his old car right in front of the air intake to the lab ventilation. He warmed up his car for a while before he started to go home after his shift, and the motor exhaust gas set off the false alarms. 

Other properties of solvents which need to be considered are boiling point, viscosity (lower viscosity generally gives greater chromatographic efficiency), detector compatibility, flammability, and toxicity. Many of the common solvents used in HPLC are flammable and some are toxic and it is therefore advisable for HPLC instrumentation to be used in a well-ventilated laboratory, if possible under an extraction duct or hood. 

A well-ventilated laboratory is still not as common as it ought to be. While local building codes may not require it, any laboratory should have a well-designed forced air ventilation system. It not only promotes worker comfort but has a strong effect on safety. 

Restrooms, laboratories, and uninterruptible power supply (UPS) systems and battery rooms should have once through ventilation. Laboratories and battery rooms should only be accessed from the outside. 

Caution. The synthesis requires autoclave equipment in a well-ventilated laboratory adequate for high-pressure reactions with carbon monoxide. 

Benzene can have both chronic and acute toxic effects. The risk of acute effects is low, since acute symptoms occur only at 1000 ppm or higher. Chronic vapor inhalation at the level of 25 to 50 ppm can cause changes in blood chemistry, and co/ rmoa7 exposure at 100 ppm can cause severe blood disorders. The OSHA exposure limits for benzene vapor are 1 ppm as an 8-hour time-weighted average and a ceiling of 50 ppm for no more than 10 min. In order to reach the level of 10 ppm in a laboratory of 750 m volume, 23 g of liquid benzene would have to evaporate into a closed atmosphere. Thus the hazards associated with the infrequent use of liquid benzene in a well-ventilated laboratory are very low. 

Mercury and its compounds are highly toxic. Air saturated with mercury vapor contains about 15 mg Hg per in In badly ventilated laboratories the amounts of Hg vapor derived from spilt mercury In the air may suffice to induce chronic mercury poisoning. The inhaled mercuiy is only very slowly excreted via the urine. I )imethylniercury (CHj)2Hg is extremely toxic and can cause irreversible damage to the central nervous system. Ozone is a strong oxidising agent and very toxic. 

Note This compound can be prepared in a well-ventilated laboratory but will stain easily take care when handling the product. 

Note This reaction should be carried out in a well-ventilated laboratory. Exercise due care when handling potassium borohydride. 

Note Work in a fume hood or well-ventilated laboratory. 

Chemists require excellent well-ventilated laboratories for safe research. They also require instruments for daily use and access to major frequently used instruments in their local department. Chemistry research sometimes requires major instruments or facilities that can only be economically supported by national facilities. 

The results of this study showed that the mean concentration of hydrogen sulfide evolved during preparation of S-A-S paving materials in the laboratory were well below the suggested maximum allowable concentration level. Peak concentrations higher than the maximum allowable levels were encountered. These, however, occur for such a short period of time that, in a well ventilated laboratory or remotely controlled commercial mixers, the preparation of S-A-S mixtures would not normally produce harmful amounts of hydrogen sulfide. 

When working with polarography, care should be taken to avoid excess exposure to mercury vapors. A well ventilated laboratory should be used (C8). 

Bromine is a skin irritant, and its vapors cause severe irritation to the respiratory tract. It will also oxidize many pieces of jewelry. Hydrobromic acid may cause skin or eye irritation. Aniline is highly toxic and a suspected teratogen. All bromoani-lines are toxic. This experiment should be carried out in a fume hood or in a well-ventilated laboratory. 

Acetone is extremely flammable and precautions must be taken not to ignite it. Avoid using large containers or quantities of acetone. Transfer the solvent in a ventilated laboratory hood. Do not use acetone near any open flame. For generation of acetone vapor, use a spark free heat source. 

Equipment for radiotherapy, cardiology, dialysis, and nuclear medicine pulmonary ventilators laboratory equipment for in vitro fertilization, diagnosis, analyzers, freezers, etc. 

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