Electrical fire protection in chemical laboratories (2)

Six, safety distance

A proper safety distance must be maintained between electrical appliances and dangerous reagents, between electrical appliances and dangerous operations, and between electrical appliances and any possible sources of danger

The pressure regulator and the reaction bottle should be separated as far as possible.

Seven, electric spark and electric heating

Some local spaces in the chemical laboratory, such as the inside of the refrigerator, the local area where the solvent flows, etc.

When the electric switch with load is turned off or on, sparks or arcs will be generated at the contact, which will cause a fire.

When a certain experimenter performed a pressurized column operation, petroleum ether splashed out, and he unconsciously pulled out the electric plug.

Some electric heaters, such as hair dryers, electric heat guns, etc.

Figure 9-9 Take out the full waste bottle from the fume hood

Figure 9-10 The organic waste liquid overflowing from the bottle mouth flows on the hair dryer and causes a fire in the fume hood

Figure 9-11 The waste bottle is broken on the ground

Figure 9-12 Formation of ground flowing fire

Eight, reasonable switch

The power-on must follow the step-by-step principle, and the power-off must follow the step-by-step principle

When turning on: the total is first and then the points are divided, that is, the main switch is turned on first, then step by step, and finally the end electrical appliances are turned on

Figure 9-13 Principles of power on and off

When closing: first divide and then general, that is, first turn off all terminal electrical appliances, then step up, and finally turn off the general switch

The advantages of doing so: First, when it is turned on or off, there is no load or less load, no electric spark or no big electric spark, which can reduce the occurrence of related accidents, especially in the explosive limit environment or close to flammable.

9.

(1) When a fire occurs due to an electrical accident, except for special circumstances, the power supply should be cut off immediately, and then the fire should be extinguished
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(2) Due to special circumstances, when it is necessary to directly extinguish the fire with electricity, fire extinguishing with water may cause electric shock, so dry powder fire extinguishers or carbon dioxide fire extinguishers should be used to extinguish the fire
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(3) For occasions where the power cannot be cut off to extinguish fires in the event of a disaster, special countermeasures must be formulated in advance to prevent accidents
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Related Links: Electrical Fire Protection in Chemical Laboratory (1)