Page 258 - Demo

Safety Supplies
Fume Hood Accessories
Velometer
The efficient operation of your school’s fume hood is essential to the well-being of you and your students. Used to check fume-hood effi- ciency, a velometer measures air velocity with readings expressed as linear feet of air per minute.
To check hood efficiency, measure the air velocity at the “face” of the hood opening, ideally at multiple locations across the face. A hood should provide air movement of at least 100 linear feet of air per minute.
Easy to use, the unit must be level during use, so a bubble level is built in. The unit is calibrated from 0 to 400 feet per minute. Accuracy is ±10%, full scale.
The carrying case is available to protect the instrument during storage.
Hood Efficiency Label
Labels should be affixed to the posts of your hood
so that you and your students know where the hood
sash should be placed to offer the highest level of protection. Adhesive backing; 21⁄2" x 1".
Smoke Generators
A great and inexpensive way to monitor air movement in your fume hood or to test the laboratory ventilation system. Once ignited, these military-type smoke generators will allow you to safely determine if your room ventilation system operates properly or if your fume hood efficiently moves air. Smoke generators also enable you to trace air movement from the inside to the outside of a building. The white/gray smoke generated is a result of a chemical reaction, so there will be no messy residue in your lab or on your clothing. If your budget does not allow a velometer to check your fume hood, then at least consider using a smoke generator to be sure that your hood efficiently moves air. Two sizes of generators are available. The 30-second type will generate approximately 4,000 ft3 of smoke. This size should be adequate to test air movements within the laboratory or fume hood. The 3-minute generator will provide almost 40,000 ft3 of smoke. This generator would be your choice if you wish to trace the exhaust path from your hood or exhaust to a remote, outdoor roof stack. Sold in packages of two generators.
1-800-452-1261
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Velometer (Vaneometer®) SE4055, etc.
Velometer Carrying Case SE1096
Catalog No.
Description
Price/Each
SE4055
Velometer (VaneometerT)
$95.95
SE1096
Velometer Carrying Case
25.20
Hood Efficiency Label SE5017
Smoke Generator SE5010, etc.
Catalog No.
Description
Price/Each
SE5017
Hood Efficiency Label
$ .64
Use Smoke Generators to Test Your Lab’s Ventilation
Many times it is difficult for administrators to understand the need for good ventilation in a chemistry laboratory. A great idea is to invite these administrators to your laboratory. Explain to them again the need for good ventilation. If they still don’t seem to understand your problem, tell them you would like them to see a demonstration.
Inform them that you will be lighting a 30-second smoke genera- tor. They are to pretend that the non-toxic smoke from the smoke generator is actually harmful invisible vapor. Light the smoke generator. Turn on your existing ventilation. The room will soon fill up with smoke. The administrators will start to leave the room because it’s getting too smoky. As they attempt to leave, stop them and ask, “Where are you going? I’m stuck in this poorly ventilated lab every day!” They now understand your problem.
Hopefully, this visual demonstration will give you the proof you need to get your ventilation problem resolved.
Catalog No.
Description
Size (DiameterLength)
Price/Pkg. of 2
SE5010
Smoke Generator, 30-second
11⁄2 x 11⁄2"
$16.05
SE5011
Smoke Generator, 3-minute
11⁄2 x 6"
33.65
Fume Hood Considerations
HOOD SAFETY
1. Do not assume that a fume hood is operating efficiently just because you hear the motor running. Check the hood using a velometer or a smoke generator.
2. Labelyourfumehoodsidepost(s)toindicatewhichsashposition(open- ing) offers the greatest protection.
3. Position the adjustable hood baffles (if furnished) to provide the most efficient air movement.
4. Do not use a fume hood as a storage area for chemicals or other materials.
5. Work as far under the hood as is practical and comfortable, but at least six inches inside the hood area as a minimum.
6. To the extent possible, use the fume hood sash as a face shield. Avoid working with the hood sash wide open.
HOOD LOCATION
1. Room drafts dramatically affect hood efficiency. Never locate a hood near or across from a window, door or air outlet/inlet.
2. Hoods should never be placed in heavy traffic areas.
3. Room air flow patterns will affect a fume hood, and these patterns should be considered before permanently locating a hood.
4. Hood exhaust should be independent of other building exhaust stacks, and the exhaust exit should be located well away from any school air inlet.
5. If multiple hoods are part of a single exhaust system, that exhaust system must be designed so each and every hood can be operated with no influence on the others in the system.
Safety Tip