Concrete and Masonry Work Safety
Many contractors perform some type of concrete work from equipment slabs to structural concrete systems. Most OSHA regulations that may apply to concrete work are found in other Subparts of the Code of Federal Regulations (such as Personal Protective Equipment).
Concrete/Masonry Safety Manuals
|
 |
| |
 |
| |
 |
However, there are some general safety methods common to
all concrete work which OSHA specifies in Subpart Q- Concrete. In this
article, the basic tool requirements for concrete work, and limited access
zones for masonry work will be outlined:
Tools and Equipment
The following are highlights of the more common
requirements for concrete tools and equipment.
-
Before using bull floats, because of their long handles, a
careful review of the area being worked should be done to determine if any
electrical equipment or wires are close. If so, the bull float handle is
required to be insulated, be of non-conductive material, or shortened to a
safe working length.
-
Masonry saws are required to have a semicircular guard
which can retain blade fragments in the event of blade breakage. This
guarding requirement is for all tools.
-
Tremies, or other concrete conveyances are required to be
secured with wire rope (or equivalent) in addition to the regular
couplings and connectors.
-
When repairs or maintenance work is performed on concrete
pumps, mixers, compressors, etc. The equipment is required to have the
power source locked out with a "Do Not Start," or similar tag at the lock.
-
Workers are not allowed to ride the concrete bucket, or
backhoe bucket.
-
When concrete buckets are used, no workers shall be
allowed to work directly under the bucket while the bucket is being
raised, or lowered into position.
Also, concrete buckets shall be routed so that the fewest (preferably no)
workers are located under it's path.
-
When placing or tying vertical reinforcing, any work
performed while on the steel, and above 6 ft. Shall have the workers using
positioning devices for fall protection. A positioning device would be a
safety belt (or harness) with a lanyard that would not allow a fall
greater than 2 ft. While safety belts are being phased out for fall
protection use elsewhere, belts are still allowed for positioning devices
since the forces arising from a 2ft. fall are not that great. Using a
positioning device, the worker climbs along the reinforcing steel into
position, then snaps a lanyard in place on each side of the belt before
working.
-
Reinforcing steel, when ends are exposed at a location
which could cause injury if a worker would fall onto or into the ends
shall be protected. Plastic end caps are commercially available for this
purpose, however, in some areas protecting the worker with a board laid
flat over the rebar ends is preferred.
-
Reinforcing steel for walls, columns, and other similar
vertical structures shall be braced to prevent overturning or collapse.
-
Roll reinforcing mesh shall be turned over (curl down), or
have it's end secured to prevent mesh from recoiling.
-
Concrete formwork shall be designed, fabricated, erected,
supported, braced, and maintained so that it will be capable of supporting
any loads (vertically and horizontally) that may reasonably be placed upon
it.
-
Concrete formwork shall not be removed unless in
accordance with plans/specification conditions, or when none are present,
then by using test cylinder results to verify adequate concrete strength.
Violations found for concrete work are not near as
frequent as for other work. Protecting rebar ends is the most common
violation found by OSHA, with lack of blade guards on concrete cutting
equipment being another frequent violation found. Another
common general requirement under concrete work applies to building masonry
walls. Whether your firm builds masonry walls, or you have them built on
your jobsites, you should understand the special requirements for a "Limited
Access Zone." Masonry Construction
The following are highlights of the requirements for
masonry work.
-
Limited Access Zone: Before work is started on a masonry
wall, a limited access zone is required to be established. The zone shall
run the length of the wall and shall extend out from the base of the
proposed wall the height of the wall plus 4 ft. (see diagram). Therefore,
a proposed wall 50 ft. long by 20 ft. high would have a limited access
zone 50 ft. long by 24 ft. wide.
-
This access zone shall be located on the side of the wall
that is not scaffolded.
-
This access zone shall only be occupied by workers who are
actively engaged in constructing the masonry wall. No other work may be
performed while the wall is being built within the zone limits.
-
When the masonry wall passes 8 ft. in height, bracing
shall be installed to prevent overturning or collapse, unless there exists
a means of supporting the wall without bracing (such as an adjoining
wall). Bracing installed shall remain in place until other permanent
supporting elements such as adjoining walls or roof structures are in
place.
-
When the masonry wall is properly braced, the limited
access zone may be withdrawn.
Training
While there are no specific references to training in this
Subpart section, safety training and discussion with your workers in the
above regulations would be necessary before working on concrete or masonry
construction. |