Occupational health and safety considerations during shutdowns
Scheduled plant shutdowns have very specific goals and targets for safety, quality, schedule, and cost. Safety performance is typically measured by the number of injury incidents (fatality + lost time incidents + medical aids) and performance compared to past shutdowns using this measure.
Achieving the safety goal requires a coordinated effort by all stakeholders. While excellent performance is expected throughout plant operations on a day-to-day basis, additional effort and rigor during shutdowns is required due to increased activity levels.
A shutdown team should be employed to manage the project. This team needs to bring together a strong, diverse and technically qualified group with the necessary experience to execute and monitor the project. Cost effectiveness, consistency and attention to the technical and regulatory demands are of utmost importance.
Working together, the project teams ultimate goals are to control the risk of worker exposure to occupational health and other safety risks associated with shutdown activities and to control risk of airborne fibres and contaminants into the plant environment.
The shutdown project team needs to have experience in plant operations, hazardous materials management (asbestos, lead, PCBs, mercury, catalyst handling), occupational hygiene and construction safety to ensure success and prevent "grinding halt" issues from occurring.
Occupational health and safety hazards associated with shutdowns
A pre-assessment of work areas should be completed by the shutdown team during the pre-planning stage of the project. The assessment should involve a discussion of work scope and a visual assessment of the work area for potential worker exposure risks. Potential risks need to be flagged and brought to the attention of the shutdown team. A detailed plan then needs to be developed for dealing with the hazards.
Occupational health and safety hazards that need to be integrated into the shutdown plan include:
– airborne contaminants (asbestos, flyash, coal dust, catalyst dusts, welding fumes, refractory ceramic fibres, lead, radiography) ;
– personal fall protection;
– falling objects;
– eye protection;
– slipping and tripping hazards;
– proper storage of gas/air cylinders; and
– confined space entry and vessel ventilation.
In dealing with airborne contaminants, the shutdown team’s goals are: to control risk of worker exposure to airborne fibre; to control risk of airborne fibre release into the plant environment; and to identify improvements to programs.
Personal fall protection
Workers exposed to falls need to meet the minimum requirements of provincial/local occupational health and safety (oh&s) regulations. If handrails or floor gratings are removed to facilitate work, workers must use approved fall restraint or fall arrest equipment. Other workers must be protected by either temporary scaffold guardrails or a flagged/ribboned area a minimum of six feet from the fall hazard. The flagged area should be not left unattended for long periods of time.
Job tasks that pose a risk of falling objects should be flagged off. A plant procedure should be developed and understood for flagging and ribboning. Past experiences that have resulted in near miss incidents with falling objects include: hoisting materials and equipment; storage of tools and material laid down inside the toe boarded area of a scaffold or work platform; passing of materials or equipment from hand to hand outside the bounds of the handrails and toe boards, work platforms and scaffolds.
Safety goggles are worn during work tasks that involve grinding, buffing, cut all saw operations. While chipping welding slag or grinding a weld, safety glasses and a welding helmet or cutting is usually acceptable protection.
Slipping and tripping hazards
Slipping and tripping hazards are common during shutdowns, and can be minimized by ensuring contractors implement proper housekeeping procedures. Wet materials such as oil, wet ash, and water, should be cleaned up immediately or flagged off as slip hazards.
Areas used for lay-down equipment must be arranged to prevent tripping hazards in common walkways. Hoses, cords, and air lines must be arranged to prevent tripping hazards in walkways. Scaffold support piping and hoist support piping (typically used for hoists at floor levels) should be flagged and ribboned for visibility.
Proper storage of gas/air cylinders
All air and gas cylinders should have main valves closed before workers leave their areas for all breaks. Regulators should be removed and safety caps installed at the end of each work shift. All cylinders should be securely stored at all times.
Confined space entry and vessel ventilation
Confined space work during shutdowns can be associated with asbestos abatement, refractory removal and replacement, chemical cleaning, catalyst handling, welding/gouging, and coating applications to name a few. In these "closed in" environment, there is usually an increased potential for worker exposure. Attention needs to be given to heat stress, personal protective equipment and ventilation requirements. All personnel entering into a confined space must have specialized training.
Vessel ventilation is critical prior to workers entering into the confined space. The key reasons vessels are ventilated are: to purge the vessel of process contaminants such as hydrocarbons, interts, steam; for comfort ventilation; for heat stress control; and to control generated contaminants. Success of ventilation is verified by gas testing prior to entry. Gas testing typically includes testing for lower explosive levels (LELs), oxygen (02) percentage, toxics such as H2S, and CO. Gas testing should be conducted with ventilation equipment both on and off and during changing conditions.
Health and safety planning and communication
An important aspect of pre-planning is to integrate occupational health and safety into the overall shutdown plan and project scope. Ownership needs to be created by the shutdown team which will involve key project stakeholders, occupational hygienists, contractors and trades.
Unique hazards occur during shutdowns that sometimes are not well understood by plant personnel. It is therefore important during pre-planning stages that a clear work scope is prepared and a plan is put into place to manage all safety and occupational hazards.
To bring increased focus on occupational health and safety during shutdowns, the following activities require additional attention:
– daily tailboard meetings with a specific occupational health and safety agenda;
– daily communication/safety meetings addressing work concerns, policy compliance, and worker safety;
– documented safe work plans and hazard assessments for all work scope;
– frequent audits and attesting;
– random and planned occupational health and safety inspections; and
– incident investigation.
Occupational health and safety budgets and resources need to be considered for collection and analysis of hazards such as asbestos, lead, refractory, silica, welding and off gasing materials. Specialized instruments such as photo-ionization detectors, flame-ionization detectors and portable GCs are excellent for quick detection, but sometimes are expensive and not easy to obtain.
Post-shutdown review and feedback
Learnings extracted from shutdown and shutdown projects are good for identifying efficiency improvements. Feedback should be encouraged from all stakeholders including plant owners, shutdown team representatives, occupational hygienists and contractors.
Call a post-shutdown meeting to discuss improvements that could be made to avoid costly mistakes in the future. Action items will come out of the meeting.
This group, with the assistance of an occupational hygienist, can develop a checklist of potential occupational health hazards that were associated with shutdown activities.
The occupational hygienist could even be brought into the pre-planning meetings in the months heading up to the shutdown to go through the checklist and to conduct a hazard assessment of the work area with the shutdown team.
Areas identified as a potential hazards should be flagged. Potential hazardous materials such as asbestos and lead should be tested, and if possible, abated prior to shutdown commencing. Areas that can not be abated should be cleaned and isolated to protect workers from airborne contaminants release.
A communication plan should be put into place during shutdowns, which include daily communication meetings with key representatives on the project. Items discussed in the meeting should b e passed onto all workers as part of their daily safety tailboard meetings.
Bill Martin, is the Regional Manager for the Alberta-based Environmental Health Professionals (EHP). EHP is a full-service provider of health and safety services including industrial hygiene, indoor air quality, training and education, safety, auditing, hazardous materials services, WCB claims management, ergonomics and contract personnel.