Safe distance (1)

Safety distance refers to the minimum space distance that must be maintained between the two in order to prevent the danger of dangerous objects (or dangerous states) to people (or machines.

There are many accidents in chemistry labs where accidents that shouldn't have happened and just happened because of not complying with a safe distanc.

Case 1

A researcher found that the eluent of the chromatography column had leaked all over the place, so she put a stack of straw paper on it, trying to absorb the eluent on the ground, and pushed the straw paper with her feet (Figure 24-54), but the result was that a lot of organic solvent volatilized , the local space reached the explosion limit, and it caught fire when it encountered the electric spark of the electric air pump next to i.

There have been many accidents caused by not paying attention to the safe use of electric air pumps, all of which are caused by insufficient safety distance between the electric spark (generated by the electric air pump) and the area where the explosion limit is locate.

Case 2

A researcher did a heating-back reaction and forgot to turn on the cooling water in the condenser tub.

Reason analysis: The outlet of the condenser tube is near the motor, and the safety distance is not enoug.

Case 3

A cleaner was washing bottles next to the washing tub against the wal.

A researcher prepares the mobile phase for column chromatography on the ground, next to the electric socket, the safety distance between the electric socket and the organic solvent is not enough, the volatilization of the organic solvent forms the explosion limit of the local space, and the electric spark meets the plug and causes a fire, see Figures 24-58.

Figure 24-58 The scene after the accident

Case 4

This is a fire accident caused by a fan being too close to an organic combustible materia.

Figure 24-59 The scene after the accident

In this case, the safety distance is obviously not enoug.