4220 Flow Meter
Appendix D General Safety Procedures
In field installations of 4220 Flow Meters and associated equipment, the safety of the personnel involved should be the foremost consideration. The following sections provide safety pro- cedures for working in and around manholes and sewers. the first section offers general safety advice. The second section deals with the special problem of hazardous gases found in sewers.
WARNING
The 4220 Flow Meter has not been approved for use in hazardous locations as defined by the National Electrical Code.
CAUTION
D.1 Practical Safety
Precautions
Before any flow meter is installed, the proper safety precau- tions must be taken. The following discussions of safety proce- dures are only general guidelines. Each situation in which you install a flow meter varies. You must take into account the indi- vidual circumstances you are in. Additional safety consider- ations, other than those discussed here, may be required.
The following procedures are those used by Black & Veatch, a respected consulting firm, and are published here by permission.
“Field personnel must keep safety uppermost in their minds at all times. When working above ground, rules of common sense and safety prevail. However, when entering manholes, strict safety procedures must be observed. Failure to do so could jeop- ardize not only your own life, but also the lives of other crew members.
“1. Hazards. There are many hazards connected with entering manholes. Some of the most common hazards are:
“Adverse Atmosphere. The manhole may contain flammable or poisonous gases or the atmosphere may be deficient in oxygen. Forced ventilation may be necessary.
“Deteriorated Rungs. Manhole steps may be corroded and not strong enough to support a man. It may be difficult to inspect the rungs because of poor lighting.
“Traffic. Whenever manholes are located in the traveled way, barricades and warning devices are essential to direct traffic away from an open manhole.
“Falling Object. Items placed near the manhole opening may fall and injure a worker in the manhole.
“Sharp Edges. Sharp edges of items in or near a manhole may cause cuts or bruises.
