Safety Precautions for Work Inside the Column

Working in the confines of the column is hazardous. Appropriate safety precautions are required to minimize the hazards. Several of these precautions are required by law (405) OSHA standards eire expected to be out soon. Some general precautions for installation, removal, inspection, and cleaning work performed inside the column are listed below. These are based on references 5,7,8,131,153,185,192,210,268,274,405, and 416, supplemented by the author s experience. 

The officer responsible for safety must set the safety requirements. Before permitting personnel entry the officer must 

The officer must be versed in the relevant statutory codes, the company safety regulations, and with the hazard and safety precautions unique to the service. The officer must not approve personnel entry unless satisfied that all hazards have been consid- 

When satisfied that all is safe, the officer can issue a written permit for entry into the column. The permit should identify the joh site, indicate date and duration, and specify all safety requirements. A qualified supervisor should accept responsibility for policing these requirements. A copy of the permit should be available at the job site emd another in the control room. The permit should be valid for no longer than one shift, or at the most, one day. Extensive guidelines for the format of such permits are described elsewhere (416). 

Any valves isolating the column, including those that need to be closed while blinds or slip plates are being fitted, must be locked shut with a padlock and chain or a similar device (210). It is a good practice to post a Danger workers in column notice at the isolation. Blinds and slip plates should be installed as close to the column as possible, and on the column side of any isolation valves, in order to avoid trapping liquid between the blind and the column (210, 275). Liquid trapping in the bonnet of an isolation valve, which was blinded on its other side, has been reported to have caused at least one fatal explosion (275). 

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