THE CONCRETE BRIDGE MAGAZINE

SPRING 2017

ASPIRE is a quarterly magazine published by PCI in cooperation with the associations of the National Concrete Bridge Council. The editorial content focuses on the latest technology and key issues in the Concrete Bridge Industry.

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S A F E T Y A N D S E R V I C E A B I L I T Y 50 | ASPIRE Spring 2017 C onfined spaces encountered during construction and maintenance of bridges present safety hazards in the construction industr y that require mitigation. The construction industr y's understanding of these physical and atmospheric hazards has increased in recent years, allowing the industry to mitigate hazards associated with confined spaces and reduce related worker issues. The hazards associated with confined spaces, such as engulfment, oxygen deficiency/ enrichment, flammable gases, and other physical hazards, are severe and can have dire consequences if not addressed properly. On May 4, 2015, the Occupational Safety and Health Administration (OSHA) issued a new standard for construction work in confined spaces, which became effective August 3, 2015. The new standard, Subpart AA of 29 CFR 1926, is intended to "prevent construction workers from being hurt or killed by eliminating and isolating hazards in confined spaces at construction sites similar to the way workers in other industries are already protected" by the confined-spaces standard. An electronic copy of the full regulatory text of the Confined Spaces in Construction standard can be found at https://www.osha.gov/ confinedspaces/1926_subpart_aa.pdf. A s d e f i n e d b y t h e s t a n d a rd , a confined space has a limited means of entry and exit, is large enough for a worker to physically enter it, and is not intended for regular or continuous o c c u p a n c y. A p e r m i t s p a c e , o n e requiring a permit, "is a confined space that may have a hazardous atmosphere, engulfment hazard, or other serious hazard, such as exposed wiring, that can interfere with a worker's ability to leave the space without assistance." G i v e n t h e i r e n c l o s e d s h a p e s , segmental concrete box-girder bridges are an obvious context in which to review confined spaces. However, given the above definitions of what constitutes a confined space, all bridge types will have some element of confined spaces and they should be identified during the project-planning phase. Once identified, these safety concerns can be mitigated through proper planning and best practices. What's New? O S H A h a s i d e n t i f i e d f i v e k e y differences between the new Confined Spaces in Construction standard and the general industry standard. The five new requirements follow: 1. M o r e d e t a i l e d p r o v i s i o n s requiring coordinated activities w h e n t h e r e a r e m u l t i p l e employers at the worksite. This will ensure that hazards are not introduced into a confined space by workers performing tasks outside the space. An example would be a generator running near the entrance of a confined space causing a buildup of carbon monoxide within the space. 2. Requiring a competent person to evaluate the worksite and identify c o n f i n e d s p a c e s , i n c l u d i n g permit spaces. 3. R e q u i r i n g c o n t i n u o u s a t m o s p h e r i c m o n i t o r i n g whenever possible. 4. R e q u i r i n g c o n t i n u o u s m o n i t o r i n g o f e n g u l f m e n t hazards. For example, when workers perform work in a storm sewer, a storm upstream from the workers could cause flash flooding. An electronic sensor or observer posted upstream from the worksite could alert workers in the space at the first sign of the hazard, giving the workers time to evacuate the space safely. 5. Allowing for the suspension of a permit, instead of cancellation, in the event of changes from the entry-conditions list on the permit or an unexpected event requiring evacuation of the space. The space must be returned to the entry conditions listed on the permit before reentry. For contractors that already abide by the general industry standard, the new confined-spaces standard for constr uction activities will likely not have a significant effect on their procedures, aside from the differences described previously. Designing for Confined Space The design stage is an excellent time to begin thinking about potential confined spaces both during bridge construction a n d d u r i n g re g u l a r m a i n t e n a n c e inspections. Each bridge type presents a unique set of circumstances during bridge inspection. Temporary and permanent hatches for construction should be considered to maximize ingress and egress of construction workers as well as to increase ventilation. This also aids the maintenance and inspection teams down the road. Simple considerations for the installation of electrical outlets for ventilation fans along with interior lighting can aid the inspection or maintenance team in their duties as well. Confined Space during Construction Planning is key to identifying upcoming hazards associated with confined spaces and ensuring that those hazards are communicated properly to the frontline worker. One best practice is for the contractor performing the evaluation to identify a space as a permit-required confined space until determined otherwise. The number of workers, their varying familiarity with the constantly changing hazards, and working in close proximity to one another are hazards addressed by the new standard and Confined Space Considerations for Bridges by John Kinkle, PCL Civil Constructors Inc. A practical look at mitigating hazards due to confined spaces

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