520 CMR 14.04
Protections for the General Public
(1) Generally. Wherever an unattended trench exists, the operation shall be secured in a safe
manner and suitable protection for the general public shall be provided. The Excavator shall
secure the unattended trench to prevent unauthorized entry when work is not in progress.
(2) Trenches on Public Ways. Access to unattended trenches opened during construction on
a public way shall be restricted by covers or barriers.
(a) Where covers are used they shall be comprised of steel metal plates no less than ¾ inch
thick, or equivalent. Covers shall be placed over the trench. Such covers shall be level and
physically secure to prevent the creation of a hazard by inadvertent movement.
(b) Where barriers are used they shall comply with the following provisions:
1. A continuous barrier not less than six feet in height shall surround the unattended
trench.
2. All barriers shall be of adequate strength and shall be supported in a manner that will
allow them to be seen by the motorist and provide a stable support not easily blown over
by the wind or traffic.
3. Trench barriers adjacent to high speed traffic may include traffic control barrels
ballasted by sandbags or temporary pre-cast concrete barriers as components.
4. Trench barriers comprised of multiple sections shall allow not more than four inches
between each section. Adjacent sections must be securely fastened to each other.
5. Any openings between the ground and barrier shall not exceed four inches. Openings
greater than four inches may be protected by solid guards of suitable materials, including
plywood or wood planks.
6. Barriers shall be at a sufficient distance from the trench to be unaffected by changing
conditions of the trench site.
(3) Trenches at Fixed Work Sites Other than on a Public Way. Access to unattended trenches
opened during construction at a fixed work site on public or private property shall be restricted
by covers or portable barriers.
(a) Where covers are used they shall be comprised of steel metal plates no less than ¾ inch
thick or equivalent. Covers shall be placed over trenches. Such covers shall be level and
physically secure to prevent the creation of a hazard by inadvertent movement.
(b) Where portable protective barriers are used, barriers of a height not less than six feet
shall be constructed surrounding the entire perimeter of the trench.
1. Barriers comprised of multiple sections may allow not more than four inches between
each section. Adjacent sections must be securely fastened to each other.
2. Openings between the ground and fence shall not exceed four inches. Openings
greater than four inches may be protected by solid guards or suitable materials, including
plywood or wood planks.
3. Fence-type barriers shall be adequately secured by vertical support members.
Fencing spaces shall not exceed four inches when measured as mesh size or between
slats.
4. Solid barriers shall not contain holes or indentations larger than four inches.
5. All horizontal support members shall be located on the trench side of the barrier.
6. The wall of a dwelling or other permanent structure of a height of not less than six
feet may serve as part of the barrier, provided it complies with all of the provisions of
520 CMR 14.04.
7. Gates and other means of egress must:
a. Comply with the size and strength provisions of 520 CMR 14.04(3)(b);
b. Be securely fastened to adjacent barrier components;
c. Allow not more than four inches between gates and barrier components; and
d. Be securely locked with a padlock, combination lock, or other suitable locking
device.
8. Barriers must be clearly marked on all sides with signs indicating "Danger - Do Not
Enter", "Authorized Personnel Only" or equivalent warning.
9. Barriers shall be placed at a sufficient distance from the trench to be unaffected by
changing conditions of the trench site.
(4) The provisions of 520 CMR 14.04 may be substituted by continuous personal monitoring
of the unattended trench by the permit holder or by person(s) under the control and direction of
the permit holder.
(5) The provisions of 520 CMR 14.04 may be substituted by backfilling the work site while
unattended.
(6) The permitting authority may require any additional, site-specific provisions it deems
necessary to protect the general public as a condition to any permit issued.