This publication applies to HYCO plants and provides design and safeguards requirements of utility and instrument gas systems. It identifies the potential hazards resulting from the connections between gases, instrument gases, and the process.

Reviews of accidents both inside and outside of the industrial gases industry often reveal that at least one of the following causes have contributed to the accident: • Hazards associated with a task were not adequately identified; and/or • Appropriate prevention and protection measures were not properly identified and/or implemented. The use of a work permit system to manage potentially hazardous work tasks should ensure that risk is reduced to an acceptable level. This publication is intended to outline the key elements of a good work permit system. A fundamental basis of European workplace and worker safety legislation is “risk assessment”. (Health and Safety Framework Directive - Council Directive 89/391/EEC of 12 June 1989 on the introduction of measures to encourage improvements in the safety and health of workers at work. For normal operating tasks and for foreseeable inspection and maintenance tasks, the employer has a general duty (which in many countries can also be a legal obligation) to provide written operating instructions and to document that sufficient measures are in place so that the risk associated with those foreseeable tasks is acceptable. In addition to written instructions for normal operations and normal inspection and maintenance tasks, every good safety management system should also include a written work permit procedure to control potentially hazardous tasks. This publication describes the key elements of a robust work process (management system) to formally manage such tasks under a “work permit”.