Does hot glass looks the same as cold glass?
Does hot glass looks the same as cold glass?
Originally Answered: Do hot and cold glassware look the same? Up to a point, yes. Below about 1200 degrees farenheit, glass doesn’t change the way it looks. This is plenty of heat to be able to burn you, which is why “cold glass looks exactly like hot glass” is a rule to keep in mind in the lab or kitchen.
Is all unauthorized experiments are prohibited?
All unauthorized experiments are prohibited. You are allowed to enter the chemical preparation/storage area any time you need to get an item. Laboratory aprons should be worn during all lab activities.
In which part of the flame should glass tubing be heated?
To fire polish glass tubing, rotate the end in the Bunsen burner using the hottest part of the flame. Heat and rotate the tube until the edges are smooth. You should be able to see this without too much difficulty. When glass is heated to high temperatures, it becomes soft and starts to behave like a liquid.
Can a biosafety cabinet be used as a fume hood?
While a biological safety cabinet (biosafety cabinet or BSC) is sometimes referred to as a ductless fume hood, the BSC does not protect from chemical vapors. Likewise, ductless fume hoods are not biological safety cabinets, but can protect from particulates when fitted with HEPA/ULPA filters.
How do you check fume hood face velocity?
Assessing face velocity results
- Check airflow velocity meter type.
- If possible, verify readings with another air velocity meter or by checking air volume using a pitot tube traverse of the exhaust duct.
- Supply voltage is correct.
- Exhaust unit inlet and outlet conditions are suitable.
What is a fume hood used for?
Purpose. Chemical fume hoods, when used properly, are one of the most reliable engineering controls in the laboratory. They protect workers by: Containing vapors, dusts, gases, and fumes generated within the hood, and removing them as air flows into the hood and then out via the laboratory exhaust system.
How does a ductless fume hood work?
Fume hoods are ventilation devices which exhaust chemical fumes, vapors, gasses, dust, mist and aerosols. However, unlike conventional fume hoods, ductless fume hoods filter out chemical fumes using activated carbon filters and recycle the air directly back to the working environment.
Which chemicals should not be stored together?
10 Sets of Chemicals Which Should Never Be Stored Together
- Chlorine. Chlorine is a common disinfectant, is widely used in swimming pools and leisure centres.
- Acetone. Acetone is often used to clean down surfaces in laboratories and manufacturing plants.
- Iodine.
- H20 (Water)
- Caustic Soda.
- Nitric Acid.
- Hydrogen Peroxide.
- Zinc Powder.
What is the OSHA recommended fume hood face velocity for fume hood air flow rates?
100 fpm
What is the recommended face velocity range for a laboratory chemical fume hood?
It is generally recommended that a fume hood’s face velocity is between 0.3 m/s (60 fpm) and 0.5 m/s (100 fpm), however, it is best to check with local safety regulations before using a fume hood because variations exist by state and by use.
What helps to optimize the flow of air in a chemical fume hood?
To optimize the performance of the fume hood, follow the practices listed below:
- Normal baffle position all slots are evenly opened.
- High temperature work such as using hot plates; lower slots are minimized since heated vapors tend to rise.
- Heavy gasses and vapors are better captured when upper slots are minimized.
What is the proper height or placement of the sash during use of the fume hood?
While performing work in the hood the sliding sash should be kept at the height designated sixteen inches (16″). This allows the sash to serve as a physical barrier between your face and the contents of the fume hood should a spill, splash, explosion or fire occur. When not in use, the sash should be kept closed.