Confined-space entry

Entry into bins, silos, rail tank cars, tank trucks, or other confined spaces used to ship or store carbon black should only be done following correct confined space entry procedures. Confined space entry procedures should include testing for carbon monoxide, carbon dioxide, and oxygen. 

Examples of confined spaces whose entry may involve extra hazards are pits, dikes, excavations, control panels, sewers, crowded areas, and vessels. The hazards frequently encoimtered in confined spaces are 

OSUA is heavily involved in the regulation of entry into confined spaces and actually mandates permit procedures. The requirements are covered in detail in Section 7.1.4. An OSHA confined space is defined in 29CFR1910.146 as having three characteristics  

An entry permit is required whenever a confined space has any of the following characteristics  

The acceptable level of a hazardous vapor will be a function of its LEL or MAC. Atmospheric testing should be done only with tested and approved equipment. The test apparatus should be calibrated frequently or immediately before use. When the work itself generates toxic or flammable vapor (e.g., welding), or when there is the possibility that such vapors will enter the space, continual monitoring is necessary. 

Oxygen concentrations should be at least 19.5%, unless air-supplied respiratory equipment is used. Where possible, positive ventilation should be used and continued as long as anyone remains in the confined space. Air should be supplied in such a way and at such a location that it must pass the worker(s) before exhausting. 

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Entry into Confined Spaces. In 1993 OSHA adopted a confined space entry rule (93) requiring employers to evaluate the workplace to (/) determine if it contains any confined spaces, (2) mark or identify such confined spaces, and (2) develop and implement a permit program for entry into such spaces. The program must include a permit system which specifies the steps to be taken to identify, evaluate, control, and monitor possible electrical, mechanical, and chemical ha2ards select and use equipment institute stand-by attendance and estabflsh communications. The reference standard (93) should be studied for details. 

Included ia the OSHA regulations are standards for safe work practices such as lock-out/tag-out and confined space entry, personal protective equipment, storage of hazardous materials, welding process, forklift operation, and requirements for fire protection. Basically, all activities within a chemical facihty are covered by OSHA standards. 

Dow Chemical Company Safety Standard on Confined-Space Entry states the following regarding confined space entiy. 

Introduction of non-flameproof electrical equipment into restricted area Mechanical isolation, e.g. conveyors, lifts Confined space entry Radioactive areas... 

Not all existing procedures or program elements of the overall health and safety program need to be incorporated into the HASP. For example, if noise is a hazard, the plan does not have to cite the entire hearing conservation program. Procedures already established elsewhere may be referenced, as applicable. In another example, if a confined-space-entry procedure is required, the HASP could reference the particular procedure which is part of the overall program. The next step would be to identify confined spaces at the worksite where the procedure applies, and then provide appropriate implementation procedures (e.g., conditions to be monitored, evaluation of the space, issuance of an entry permit). If special operational procedures apply to the worksite, they can be attached to the HASP using an appendix. 

The contractors SSAHPs at Sites B, F, and K had general confined space provisions but lacked site-specific confined space procedures. For example, SSAHPs for the Site K contractor and subcontractor had written confined space entry programs, but the programs did not establish site-specific rescue procedures or identify the confined space hazards present on the site. The job hazard analyses for both programs failed to address site maintenance tasks that could involve confined space entry and hot work hazards. The programs also failed to identify the specific person or position responsible for supervising confined space entry procedures and the location of permit-required confined spaces on site. Interviews with both contractors indicated confusion about rescue procedures. 

Employees stated that they had received confined space training and were prepared to perform confined space rescue, but they had not rehearsed rescue procedures. In addition, the confined space entry permit form for both contractors did not ask for all required information. For example, the form did not require documentation of the duration for the permit, the intended communications procedures for entry operations, or documentation of hot work performed during confined space entry operations. Completed permits did not contain documentation of hot work performed during confined space entry operations, even though hot work had been performed during such operations at least twice during the project. 

Similarly, the Site B contractor s SSAHP provided corporate policy and procedures for permit-required confined space entry but lacked the site-specific detail necessary to describe the application of the corporate policy to procedures at the site. For example, the SSAHP did not identify specific components of the thermal treatment unit that presented confined space hazards, nor did it describe the specific circumstances or procedures that would require employee entry into these areas. In addition, the plan stated that the contractor would maintain an onsite employee confined space rescue team, but did not identify the members of this team. The SSAHP for Site F also contained a generic confined space entry program but did not identify the specific location of confined space hazards present at the site. 

Contractors at Sites E, H, and J had documented confined space programs but had not fully implemented these programs. The Site H contractor had established a permit-required confined space entry program consistent with HAZWOPER requirements however, onsite procedures were not completely consistent with the written program or OSHA requirements. For example, the confined space permit form used at Site H was not the form included in the written program. The audit team also found evidence that employee training was insufficient for safe... 

Signed copies of confined space entry forms... 

Contract employees must perform their work safely. Considering that contractors often perform very specialized and potentially hazardous tasks, such as confined space entry activities and nonroutine repair activities, their work must be controlled while they are on or near a process covered by PSM. A permit system or work authorization system for these activities is helpful for all affected employers. The use of a work authorization system keeps an employer informed of contract employee activities. Thus, the employer has better coordination and more management control over the work being performed in the process area. 

Safe work practices for hazards control lockout/tagout, confined space entry, procedures for opening process boundaries and entrance control for maintenance... 

The hazards of management-controlled nonroutine work in the process areas must be communicated to affected individuals. The work permit prescribes the procedures that must be followed to get the permit. Work authorization procedures specify lockout/tagout, line breaking., confined space entry, and hot work authorization through clear steps leading to job completion, closure, and return to normal. 

Where such internal inspection work is carried, out a safety checklist and processes for confined space entry permit system and tag-out/lock-out MUST be undertaken before any person enters the boiler. The inspection of waterside surfaces should be carried out by a suitable qualified person and will benefit from employing either an instant camera or a video camera (Horoscope or similar fiberoptic-based device) to record any parts of the boiler where corrective action is needed. 

All confined space entry permits procedures and other safety regulations must be followed. 

Injuries and fatalities from asphyxiation are often associated with personnel entry into inerted equipment or enclosures. Guidance on safe procedures for confined space access are provided by OSHA (OSHA, 29 CFR 1910.146, Confined Space Entry Standard, 2000), the American National Standards Institute (ANSI, Z117.1, Safety Requirements for Confined Spaces, 2003), Hodson (Hodson, Safe Entry into Confined Spaces, Handbook of Chemical Health and Safety, American Chemical Society, 2001), and BP (BP, Hazards of Nitrogen and Catalyst Handling, 2003). OSHA has established 19.5 vol % as the minimum safe oxygen concentration for confined space entry without supplemental oxygen supply (see Table 23-18). Note that OSHA imposes a safe upper limit on 02 concentration of 23.5 vol % to protect against the enhanced flammability hazards associated with 02-enriched atmospheres. 

Nonessential personnel report to safe assembly areas. Stop all hot work and confined space entry Nonessential Personnel... 

Confined space entry ° Hearing protection ° Respiratory protection ° Bloodborne pathogens... 

Confined Space Entry Program, 29 CFR 1910.146, U.S. Department of Labor, Occupational Safety and Health Administration, Jan. 14,1993. 

Disaster was adverted when a safety technician entered the control room as part of an unrelated confined space entry permit. The technicians portable oxygen measuring instrument was activated and in the operating mode. The low-level oxygen alarm sounded, warning the people in the control room of the very serious condition. 

The mechanical integrity procedures must also embody the safe work practices as well as the detailed equipment procedures. Safe work practices include Lock and Tag, Confined Space Entry, Welding, Burning and Open Flame, and similar essential personnel safety procedures. Detailed equipment procedures include generic procedures, equipment specific procedures, and manufacturers procedures. 

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