Excavation and Trenching 2018 Stand Down. Jim Shelton, CAS Houston North Area Office

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1 Excavation and Trenching 2018 Stand Down Jim Shelton, CAS Houston North Area Office

2 Why a Trenching Safety Stand Down?

3 Workers Die and Get Injured

4 Not All Publicity is Good Publicity

5

6 BLS Fatalities by Event or Exposure Excavation or Trenching Cave-In 651XXX

7 BLS LWDI by Event or Exposure Excavation or Trenching Cave-In 651XXX

8 OSHA Reported Trenching Fatalities Trenching Injuries & Deaths Trench-Related Fatalities Trench-Related Reported Injuries

9 Competent Person A competent person means one who is capable of identifying existing and predictable hazards in the surroundings, or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them Duties of a competent person include, but are not limited to:

10 Competent Person Designs structural ramps used as a means of access or egress from excavations Monitors water removal equipment and operations Conducts daily inspections of excavations, the adjacent areas, and protective systems for: Evidence of potential cave-ins Indications of failure of protective systems Hazardous atmospheres Other hazardous conditions

11 Competent Person Conduct inspections prior to the start of work and as needed throughout the shift Inspect after every rainstorm or other hazard increasing occurrence Inspect excavations subjected to runoff from heavy rains

12 Competent Person Remove employees where there is evidence of a situation that could result in a possible cavein, indications of failure of protective systems, hazardous atmospheres, or other hazardous conditions from the hazardous area until the necessary precautions have been taken to ensure their safety Examine excavations less than 5 feet in depth to determine that protective systems are not needed based on cave-in potential

13 Competent Person Examine damaged protective systems and evaluate its suitability for continued use. If the competent person cannot assure the material or equipment is able to support the intended loads or is otherwise suitable for safe use, then such material or equipment shall be removed from service, and shall be evaluated and approved by a registered professional engineer before being returned to service

14 Competent Person Ensure trenching and excavation work has a competent person You should also verify they are competent

15 Examples of FY 17 Cave-In Incidents Two employee were working in a trench deep preparing a trench for the installation of a new sanitary sewer line. The straight cut walls of the trench caved in covering the workers and a fire hydrant came loose from the water main from which it was attached filling what remained of the trench with water The backhoe operator was digging to find the sewer stub and struck it with the backhoe bucket breaking the stub going to the sewer. The operator dismounted the excavator and climbed in the unprotected excavation to investigate and while digging the dirt away from the sewer stub the trench wall caved in burying the employee in the trench

16 Examples of FY 17 Cave-In Incidents Employee was installing a test ball in the plumbing to test the line for leaks. The side wall of the trench caved in covering him with dirt up to his abdomen crushing and asphyxiating him The employee was installing drainage strip on the interior side of the trench when it became folded and employees were unable to pour gravel onto it. Employee entered the trench, approximately 40 from strip needing to be corrected from the backfilled side and ran to go adjust the strip. The employee adjusted the strip to its desired position when the trench caved in covering his entire body underneath

17 Examples of FY 17 Cave-In Incidents Employee was using a tape measure to get a measurement inside of a 6-1/2 unprotected excavation vertical side walls when it collapsed. He was struck in the midsection by the collapsing excavation wall and became buried from the midsection down. The impact of the falling material crushed his internal organs rupturing his aorta causing severe internal blood loss. He succumbed to his injuries and was pronounced dead at the scene Employee was shoveling dirt into a pile at bottom of a trench when the earthen wall sheared off slamming him into a concrete retaining wall causing head trauma and death

18 Examples of FY 17 Cave-In Incidents Putting a collar on a newly installed sewer pipe in an excavation when the unprotected side wall of the 9 deep trench collapsed on him causing hid death Employee was directing a crane operator while standing inside excavation to install a new cesspool when the ground gave away and collapsed and he fell into the hole. He was engulfed and died

19 Examples of FY 17 Cave-In Incidents Employees began excavating under a foundation. They began hand digging a pit with shovels and an electric impact hammer to loosen the earth. During this process a co-worker was observing the employee excavate the last stages of the pit when an unsupported 2,600 lb rock that formed part of the foundation and which was located on the ceiling of the area that was excavated dislodged crushing and killing the employee Employee was in the trench cleaning up his tools and equipment when the trench collapsed trapping him against the opposite side causing a crushing injury to the chest area

20 Examples of FY 17 Cave-In Incidents Employee was inside of a 7.5 trench raking rock. The protective system was a slide rail system. The storm drain did not fit inside of the trench and the spreader would not go down as designed so a 15x8 trench plate and a shore jack was used to secure the metal trench plate to the trench wall. The trench caved in and the 4,900 lb trench plate fell on him crushing him and causing fatal injuries Employee was working at the bottom of an excavation in an agriculture field to connect a 3" lateral drain pipe into a 12" main pipe when the east side wall of the excavation caved in pushing him to the west side wall and burying his body up to his head. He was brought to a local hospital where he later passed away

21 Examples of FY 17 Cave-In Incidents Employee was connecting pipes and working with a trowel and mortar when he stepped outside of protective steel trench box to work in the 20 x 10 deep trench. A 3 x 2 piece of clay became dislodged under concrete and fell compressing/crushing him causing death from blunt force head and craniocerebral trauma Workers were installing water main lines in an excavation approximately 99 long by 2 8 wide and 7 deep. Birch shoring boards and hydraulic jacks for cave-in protection were installed. The worker was in the trench for approximately five minutes backfilling within the shoring boards. A coworker noticed that the trench had collapsed and saw a hard hat in the collapsed dirt and called for help. The worker was suffocated by the weight of the collapsed dirt

22 FY 17 MFC Fed OSHA Subpart P Standard Cited Narrative (a)(1) 419 Each employee in an excavation shall be protected from cave-ins by an adequate protective system designed in accordance with paragraph (b) or (c) of this section except (c)(2) 201 A stairway, ladder, ramp or other safe means of egress shall be located in trench excavations that are 4 feet (1.22 m) or more in depth so as to require no more than 25 feet (7.62 m) of lateral travel for employees (k)(1) 183 Daily inspections of excavations, the adjacent areas, and protective systems shall be made by a competent person for evidence of a situation that could result in possible cave-ins, indications of failure of protective systems, hazardous atmospheres, or other hazardous conditions. An inspection shall be conducted by the competent person prior to the start of work and as needed throughout the shift. Inspections shall also be made after every rainstorm or other hazard increasing occurrence. These inspections are only required when employee exposure can be reasonably anticipated

23 FY 17 MFC Fed OSHA Subpart P Standard Cited Narrative (j)(2) 155 Employees shall be protected from excavated or other materials or equipment that could pose a hazard by falling or rolling into excavations. Protection shall be provided by placing and keeping such materials or equipment at least 2 feet (.61 m) from the edge of excavations, or by the use of retaining devices that are sufficient to prevent materials or equipment from falling or rolling into excavations, or by a combination of both if necessary (k)(2) 48 Where the competent person finds evidence of a situation that could result in a possible cave-in, indications of failure of protective systems, hazardous atmospheres, or other hazardous conditions, exposed employees shall be removed from the hazardous area until the necessary precautions have been taken to ensure their safety (h)(1) 25 Employees shall not work in excavations in which there is accumulated water, or in excavations in which water is accumulating, unless adequate precautions have been taken to protect employees against the hazards posed by water accumulation. The precautions necessary to protect employees adequately vary with each situation, but could include special support or shield systems to protect from cave-ins, water removal to control the level of accumulating water, or use of a safety harness and lifeline.

24 FY 17 MFC Fed OSHA Subpart P Standard Cited Narrative (i)(3) 18 Sidewalks, pavements, and appurtenant structure shall not be undermined unless a support system or another method of protection is provided to protect employees from the possible collapse of such structures (b)(2) 15 Maximum allowable slopes, and allowable configurations for sloping and benching systems, shall be determined in accordance with the conditions and requirements set forth in appendices A and B to this subpart (j)(1) 14 Adequate protection shall be provided to protect employees from loose rock or soil that could pose a hazard by falling or rolling from an excavation face. Such protection shall consist of scaling to remove loose material; installation of protective barricades at intervals as necessary on the face to stop and contain falling material; or other means that provide equivalent protection (d) 13 Employees exposed to public vehicular traffic shall be provided with, and shall wear, warning vests or other suitable garments marked with or made of reflectorized or highvisibility material

25 Safety Quiz An excavation requires protection from cave-in at what depth? 4 Feet 5 Feet 6 Feet 10 Feet 5 Feet (a)(1)(ii) Unless it s in stable rock or an examination by a competent person determines an excavation less than 5 feet doesn t pose a cave-in hazard

26 Safety Quiz What are four types of ways workers can be protected from cave-ins? Sloping Benching Shielding Shoring

27 Safety Quiz What is a competent person considered in an OSHA standard? One who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees and has the authorization to take prompt corrective action to eliminate them (b)

28 Safety Quiz A means of egress from trench excavations is required when the depth of the excavation is feet deep or more in depth? 3 Feet 4 Feet 5 Feet 6 Feet 4 Feet (C)(2) and must have no more than 25 feet of lateral travel to reach

29 Safety Quiz The estimated location of utility installations such as sewer, telephone, fuel, electric, water lines that may reasonably be expected to be encountered must be determined prior to opening an excavation True False True (b)

30 Safety Quiz Would a 1-1/2 : 1 benched ratio be acceptable for a Type C soil? Would a 1 : 1 benched ratio be acceptable for a Type C soil? No The ratio is 1-1/2 : 1 but there is no benching chart for benching Type C soils. The chart shows a simple slope Appendix B, B-1.3 No The ratio is 1-1/2 : 1, not 1 : 1 Yet how many excavation do we see one bucket down and one bucket over?

31 Safety Quiz Trench excavations require a daily inspection by a competent person True False True (k)(1) Prior to the start of work and as needed throughout the shift, after rain storms or other hazard that occurs when there is employee exposure anticipated

32 Safety Quiz Spoil piles must be kept a minimum of away front the edge of the excavation? 2 feet (j)(2) Employees must be protected from materials and equipment that may pose a hazard by falling or rolling into the excavation. In place of the two foot rule you can use retaining devices that will prevent materials and equipment from entering the excavation or use both methods

33 Safety Quiz What do you think the most frequently cited willful trenching violation usually is? Failure to use a protective system such as sloping, benching, shielding (e.g. trench box) or shoring (a)(1) was cited willful 22 times by Federal OSHA in FY 2017 It was also the number one excavation standard cited as a repeat. Forty times in FY 2017

34 Why We Have Excavation Rules Trench Dimensions: 8 deep, 12 long, 11 wide, vertical walls. Employees were boring under the roadbed to install a 6 sewer line tap on south end of trench The ground surface on the road side of the trench has no fissure. Time12:42 PM.

35 Why We Have Excavation Rules The ground surface on the road side of the trench begins to fissure. Time : 1:05:50 PM. The ground surface/wall on the road side of the trench collapsing. Time : 1:06:16 PM.

36 Why We Have Excavation Rules Collapsed wall. The portion of the wall that fell was15 wide by 9 long by 5 deep. Weight of the dirt was conservatively calculated to be 6,187 pounds just over 3 tons It took 26 seconds from the appearance of the fissure to the collapse of the wall. The employees would have been struck-by the collapsed wall while installing the sewer line.

37 OSHA Site Assessment Questions Is the cut, cavity, or depression a trench or an excavation? Is the cut, cavity, or depression more than 4 ft (1.2 m) in depth? Is there water in the cut, cavity, or depression? Are there adequate means of access and egress? Are there any surface encumbrances? Is there exposure to vehicular traffic? Are adjacent structures stabilized? Does mobile equipment have a warning system? Is a competent person in charge of the operation?

38 OSHA Site Assessment Questions Is equipment operating in or around the cut, cavity, or depression? Are procedures required to monitor, test, and control hazardous atmospheres? Does a competent person determine soil type? Was a soil testing device used to determine soil type? Is the spoil placed 2 ft (0.6 m) or more from the edge of the cut, cavity, or depression? Is the depth 20 ft (6.1 m) or more for the cut, cavity, or depression? Has a registered professional engineer approved the procedure if the depth is more than 20 ft (6.1 m)?

39 OSHA Site Assessment Questions Does the procedure require benching or multiple benching? Shoring? Shielding? If provided, do shields extend at least 18 in (0.5 m) above the surrounding area if it is sloped toward the excavation? If shields are used, is the depth of the cut more than 2 ft (0.6 m) below the bottom of the shield? Are any required surface crossings of the cut, cavity, or depression the proper width and fitted with hand rails? Are means of egress from the cut, cavity, or depression no more than 25 ft (7.6m) from the work? Is emergency rescue equipment required?

40 OSHA Site Assessment Questions Is there documentation of the minimum daily excavation inspection? These are good questions to start assessing the hazards and safety procedures being used by an excavation company. It doesn t cover everything, it s a start. The competent person should be able to walk you through what was done. If they can t, what does that tell you about their competency?

41 What Hazards Can You Find?

42 National Trench Safety Stand Down Excavation safety information can be found on the NUCA stand down webpage: OSHA Excavation and Trenching Webpage: n/index.html The Houston North excavation stand down flyer has additional information and resources. If you would like a copy Jim Shelton at shelton.james@dol.gov

43 OSHACON 2018 OSHA Construction Conference 2018 September 13-14, 2018 Houston Marriott Westchase Speaker abstracts being taken at:

44 Questions? Houston North Area Office Joann Figueroa, Area Director Jim Shelton, CAS 690 S. Loop 336 W., Suite 400 Conroe, TX Keep up to date with the Houston North Area Office list. Contact Jim Shelton at the above

45 Disclaimer Serious Incident Reports (SIRs) and Fatality cases and incidents are an estimate and should not be considered a exact count or a statistical study or referenced in that way Incidents are generally categorized by event and focus four factors in broad categories and may include related activities This information has been developed by an OSHA Compliance Assistance Specialist and is intended to assist employers, workers, and others as they strive to improve workplace health and safety. While we attempt to thoroughly address specific topics [or hazards], it is not possible to include discussion of everything necessary to ensure a healthy and safe working environment in a presentation of this nature. Thus, this information must be understood as a tool for addressing workplace hazards, rather than an exhaustive statement of an employer s legal obligations, which are defined by statute, regulations, and standards. Likewise, to the extent that this information references practices or procedures that may enhance health or safety, but which are not required by a statute, regulation, or standard, it cannot, and does not, create additional legal obligations. Finally, over time, OSHA may modify rules and interpretations in light of new technology, information, or circumstances; to keep apprised of such developments, or to review information on a wide range of occupational safety and health topics, you can visit OSHA s website at