COLLECTION SAFETY SYSTEM PART 1 (SAFETY MEASURES)

COLLECTION SYSTEM SAFETY

The construction of sewers should be in accordance with standard design, with special attention

to self-cleaning velocities, good alignment, proper spacing of manholes, and adequate provision

for ventilation. These design standards when followed, will provide for a safer work

environment. However, there are several other points of safety that are of major importance.

Safety Measures

Entering a manhole is a potential safety hazard, which may be more serious than the employee

would think. The employee should be fully aware of the following facts:

1) Poisonous and explosive gases, such as hydrogen sulfide, carbon dioxide, ammonia, and

methane may concentrate in a manhole. Overexposure to these gases may cause an explosion.

2) The manhole itself may not be in very good condition. The wall bricks may falloff and/or the

manhole steps may be corroded to such an extent that they will not support your weight.

safety measures continued

3) Objects can fall through the manhole opening onto the employee's head. Sharp objects such

4) as broken glass, razor blades, etc. may cut your hands and feet. A sudden increase in the

sewage flow, in a large sewer, can draw and carry a person away. The employee could

accidentally fall into a manhole due to various reasons.

5) An open manhole, without a guard and safety markers around it, is extremely

dangerous both to the traffic above and the person (s) working in the manholes.

6) In order to avoid accidents, the proper safety precautions should always be practiced when

entering a manhole. This should be done even when entering a manhole for a short period of

time. The Project Supervisor or Foreman should review with his employee’s detailed information

on the safety procedures that are being used. This should be done before beginning any manhole

investigation project.