Two workers recently were killed in accidents that occurred during the de-watering of natural gas pipelines, a process conducted following the construction of the pipelines. The victims were killed when they were struck by temporary de-watering piping, which was not properly anchored and broke loose from its coupling from excessive air pressure. The Occupational Safety and Health Administration (OSHA) and the Office of Pipeline Safety (OPS) urge that all persons working on, or in close proximity to, de-watering processes be alerted to this serious hazard and take appropriate steps to prevent death or serious injury.

Purpose

The purpose of this Safety and Health Information Bulletin (SHIB)/Advisory Bulletin (ADB) is to highlight:

• potential hazards associated with pipeline de-watering operations;
• work practices and guidelines that can reduce the potential for unexpected separation of temporary de-watering pipes; and
• training that can help to protect employees from these hazards.

Accident Description

The OSHA Allentown and Wilkes-Barre Area Offices recently investigated two fatalities that occurred in conjunction with de-watering processes associated with newly constructed natural gas pipelines. In both cases, the temporary de-watering piping violently separated from its couplings, striking and fatally injuring employees. In one instance, the separated section of pipe was thrown 45 feet from where it had been attached to the temporary de-watering valve. OSHA determined that a major contributing factor to both of the accidents was temporary de-watering pipelines that were not adequately secured to prevent the piping from moving or separating. In one case, the failure occurred at a pipe coupler that was not being used within the safe tolerances established by the manufacturer.

Background

After a pipeline is laid, a hydrostatic test is conducted to ensure its integrity. Hydrostatic testing may also be conducted during the service life of the pipeline to evaluate its operational integrity.

The hydrostatic test consists of pumping water into the pipeline, “pressuring up” the line to specified test pressures, and holding that pressure for a discrete period of time in accordance with applicable regulations and guidelines, including regulations promulgated by OPS. After completion of the hydrostatic test, the pressure is relieved and the water is removed from the pipeline (de-watering).

The de-watering process involves connecting a temporary de-watering line (figure 1) to the main pipeline with mechanical couplers and adequately securing the temporary de-watering line to prevent displacement. A de-watering “pig” (figure 2) is then forced through the main pipeline using several hundred pounds pressure of compressed air. As the pig is forced through the pipeline with air pressure, the water remaining in the line from hydrostatic testing is pushed out of the main pipeline through the temporary de-watering line.

The condition of the couplings, which are used to attach the de-watering pipe to the main gas line and other temporary de-watering pipe sections, likely contributed to one of the accidents that OSHA investigated. In that case, the failure occurred at a pipe coupler that was not within the manufacturer’s established tolerances. With the added pressure of the de-watering process, a damaged or improper coupler could contribute to the separation of temporary pipe sections. It is imperative that all connections and fixtures be in proper working condition. The groove installed on the pipe needs to be conformed to manufacturer specifications and guidelines, be properly fitted, as specified by the engineer who develops the de-watering plan, and chosen for the application.

Excessive and Variable System Pressures

During de-watering, the de-watering pig is pushed through the pipeline using compressed air. The pressure exerted on a piping system, including the de-watering piping, can be much greater than that indicated by gauges on the air compressor(s). Where terrain includes hills, slopes, or other changes in elevation, the pressure on the de-watering system can be increased significantly by the hydrostatic head pressure, adding to the potential for pipe separation.

It is possible for the pig to become stalled or stuck in the line. Whether the pig becomes stalled because of air flow around the pig or stuck because of debris inside the pipe or faulty seals, freeing the stuck pig can be problematic. At times, workers will use increased air pressure to attempt to move the pig. While increasing the line pressure is an accepted practice, the safe pressure limits of the pipeline and connections must never be exceeded. If the pressure limits of the main piping or de-watering systems are exceeded, there may be a catastrophic failure of the pipe, or more likely, the pipe connections.

Fittings, such as elbows (figure 6) in piping systems, and other factors also can contribute to pressure variation as the pig passes through the piping. Forces associated with those pressure changes can be transferred to temporary piping systems and cause movement and ruptures in connections and piping. Employers should consider the forces involved, and they should design and install anchoring systems to properly restrain or control de-watering piping.

Lack of Training

It is imperative that employers train employees who perform or work near hydrotest de-watering operations. Employers engaged in construction activities are required by the OSHA standards to “instruct each employee in the recognition and avoidance of unsafe conditions and the regulations applicable to his work environment to control or eliminate any hazards or other exposure to illness or injury.” 29 CFR 1926.21. Employers need to ensure that employees involved in de-watering of pipelines understand the potential hazards of the pressurized lines and the precautionary measures and controls necessary to protect themselves and others working in the vicinity.

Exclusion Zone

During the testing and de-watering processes, there may be hazards that may not have been completely controlled. This might include the possibility of unexpected high pressure in the pipe from internal malfunctions or irregularities, as well as failure of the pipe itself under full test pressure from undetected imperfect welds. Such situations may exceed the designed capacities of the anchorages. Therefore, the access to the test zone may be limited to only those persons who are necessary to perform the test.

Conclusions

It is recognized industry practice to anchor or restrain de-watering piping in order to prevent death or serious injury from de-watering pipeline separation. Complete engineering analyses should be performed to determine requirements for the installation and use of de-watering systems. Engineering designs and installation techniques should be developed for these temporary pipelines. In addition, employees installing temporary pipelines should be trained in these designs and techniques, and they should follow them when installing these temporary systems. Employers also should ensure that couplings and piping systems are sound and can withstand the pressures involved.

Recommendations

While there is no specific OSHA standard addressing de-watering of pipelines, the Occupational Safety and Health Act requires employers to provide a workplace that is “free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees.” 29 U.S.C. 654(a)(1). To this end, employers need to ensure that proper procedures are followed and that employees who perform de-watering processes are adequately trained and knowledgeable about proper procedures for restraining or anchoring of de-watering lines. The following guidelines will help reduce the risk of injury to employees involved in de-watering activities:

• Study the piping system. During the initial planning stage of a de-watering operation, an engineering analysis of the existing and temporary piping system should be performed to identify the pressure associated with fluids and other forces that could adversely affect the integrity of the pipeline or the stability of the drainage and its components. The employer should design the de-watering system and develop installation techniques based on the expected forces of the particular project. Alternatively, designs and techniques could be developed for a “worst case” scenario that could be applied to all de-watering projects.
• Anchor the de-watering lines. It is accepted industry practice to adequately anchor or secure de-watering piping to prevent movement and separation of the piping. Employers should establish effective anchoring systems based on expected forces and ensure that the systems are used during de-watering projects.
• Ensure condition of couplings and parts. All couplings and parts of the de-watering system need to be properly selected for their application. The associated piping which the couplings connect is a significant variable in the entire mechanical piping system. The couplings are manufactured in a controlled environment, and variations in the quality of the couplings should be limited. Employers should ensure that couplings are within manufacturer’s tolerances and free of damage that may result in connection failure. A chain is only as strong as its weakest link – in de-watering piping systems, the weakest link frequently is the temporary de-watering pipe connections.
• Provide adequate employee training. This training should instruct employees on de-watering installation designs and techniques, including proper coupling and anchoring methods. Employers need to ensure that employees understand the potential hazards of improperly installed de-watering systems, provide employees a means of determining whether the pipe groove meets manufacturer’s tolerances, and the procedures they should implement to protect themselves and others working around them.
• Proper Procedures. Employers should ensure that proper installation and de-watering procedures are followed on the job site.

To acknowledge reading this incident review please leave a comment or discuss incident or add hazard.

References

1. American Petroleum Institute (API). Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations. API RP 54-1999, Section 12.4.3.
2. American National Standards Institute (ANSI). Power Piping. ANSI B31.1-1973, Section 121.2.
3. U.S. Army Corps of Engineers (USACE). Safety and Health Requirements Manual. EM 285-1-1, 1996 Section 20.
4. Federal Pipeline Safety Regulations. 49 CFR Part 192 & Part 195.

More info: https://www.osha.gov/dts/shib/shib062104.html

 

What is a near miss?

Please comment below an example of a near miss.

Description: There is a province-wide fire ban in effect. The fire ban expands the fire restriction that was enacted on May 3 in the Forest Protection Area. All open fires, including campfires and charcoal briquettes, are prohibited. The use of incendiary targets is also banned. Portable propane fire pits and gas or propane stoves and barbeques designed for cooking or heating are allowed. The fire ban applies to Alberta’s Forest Protection Area and all counties, municipal districts and special areas, and provincial parks and recreation areas. The fire ban does not apply to cities, towns, villages, summer villages, or federal lands, such as national parks. Many of the jurisdictions that are not covered by the provincial fire ban have already put complementary fire bans in place and we encourage those that have not to do so. Recreational users of OHVs are encouraged to discontinue use until the wildfire hazard subsides. If use of these vehicles is required for industry personnel only, please take extra precautions and clean debris from hot spots regularly. The fire ban will remain in place until further notice. Every precaution is being taken to ensure no new preventable fires are started in the coming days that will put additional strain on the province’s firefighting resources.

Recently a fatality occurred during pipe handling operations on a deepwater drilling unit. A rig employee’s head was caught between the pipe handler’s lower travel assembly and a vertical support stanchion (pinch/crush point of 4 inches) as the pipe handler was being traversed across the pipe bay to the catwalk to retrieve a joint of pipe. The deceased was acting as a spotter for the pipe handler operator at the time of the incident and the pipe handler operator did not observe the incident due to his obstructed view of the spotter. The BOEM (formerly MMS) investigation revealed that unidentified crush points existed between the lower travel assembly and the vertical support stanchions of the trolley system. It was concluded in part, from the investigation that the pipe handler operator failed to confirm an “all clear” with the spotter and failed to exercise his Stop Work authority when he lost site of the spotter. The Lessee/Operator failed to provide the necessary additional oversight to ensure that the pipe handler operation was conducted in accordance with their lifting policy. The drilling company’s line management also failed to:

• Provide a more formalized training program to include the hazards associated with the operation of the pipe handler.

• Identify the specific pipe handler operational tasks, hazards and respective mitigations in order to develop and implement guidelines for personnel working around the strong-back area.

• Provide additional onsite supervision to both the Operator and Spotter during the pipe handler operation.

• Properly implement their Management of Change policy with respect to new personnel in new positions. The company’s Management of Change policy was also identified as being too complex to implement. Therefore, BOEM recommends the following to Lessees/Operators and their Drilling Contractors for any type of overhead trolley beam mounted crane (trolley crane) operation, including but not limited to a pipe handler:

• Inspect trolley crane operations with the intent to identify all potential hazards and mitigations (including pinch/crush points), and communicate these findings with all necessary personnel.

• Review Stop Work authority programs with their personnel, while stressing the importance of the individual’s responsibilities and authority to exercise Stop Work as necessary.

• Review trolley crane training programs to ensure that the program covers not only the proper operation of the equipment, but also includes the limitations, capabilities and potential hazards. If the training includes onsite hands-on training, the verification/certification should be done by senior facility management.

• Review the Management of Change policy for clarity and to ensure the program recognizes and manages changes, conditions and inactions in a given situation or unexpected events.

• Install and maintain safety barriers (signage, red zones, tiger striping, temporary barrier tape, handrails, etc.) to prevent access to the trolley crane’s traversing path.

• Clear the trolley crane’s path of general storage. Telephone, intercoms or stored items located under the trolley crane should be removed and relocated to a safer area.

• Consider the feasibility of installing cameras or mirrors in areas where the trolley crane operator’s view is obstructed.

• Consider the feasibility of re-engineering the trolley crane to possibly eliminate any additional Spotter involvement.

• Conduct pre-tour meetings for all tours, including short change crews. The short change crew involves multiple employees filling new roles and/or not working on their normal crew shift.

A man is dead after a workplace incident near Redwater, Alta. on Wednesday.

The man was working in a tower at the Pembina pipeline plant, using a breathing mask with supplied oxygen when he became distressed, an Occupational Health and Safety spokeswoman said.

A safety watch employee attempted CPR but was unable to revive the worker, who died on scene.

Occupational Health and Safety is investigating.

On April 28, people across Canada stop to remember workers killed, injured or disabled on the job.

With deep sadness, we confirm Alberta lost 125 men and women to workplace injury or illness in 2015. Take time to remember them on April 28. 

Misuse of Beam Clamps as Ground
The Bureau of Safety and Environmental Enforcement (BSEE) has identified a potential safety issue in regard to the use of beam clamps on many Outer Continental Shelf (OCS) facilities. It is determined that the use of beam clamps as grounding conductors could potentially cause fires
and present electrical hazards to personnel.
Many OCS facilities are utilizing beam clamps as current carrying external ground to meet the requirements in the API RP 14F. The beam clamps are approved by Underwriters Laboratories (UL) and Factory Mutual Research Corporation (FM) to mount and support conduit and cable from structural beams, not as temporary or permanent external equipment grounding conductors. Example below:

API RP 14F & 14FZ § 6.10.3.1 states: “Grounding of electrical equipment on fixed and floating offshore petroleum facilities in a positive manner is of particular importance because personnel standing on steel decks or in contact with steel framing present a low impedance path to ground, effectively grounded. In addition, the dampness and salt spray contribute to the breakdown of insulation and to the possibility of leakage on the surface of insulators and similar devices. On platforms with wooden or concrete decks, equipment-grounding conductors should be installed between electrical equipment and a grounding network. It is recommended that all metal equipment, such as buildings, skids, and vessels be grounded to the steel structure or grounding network. Exposed, noncurrent-carrying metal parts of fixed equipment that may become energized because of any condition shall be grounded. Equipment that is welded to the structure or deck is considered to be adequately grounded. The physical contact obtained when equipment is bolted to a steel structure is not necessarily an adequate effective ground because of paint and possible corrosion. Exposed, noncurrent-carrying metal parts of portable electrical equipment shall be grounded through a conductor in the supply cable to the grounding pole in the receptacle.”

API RP 14F & 14FZ both make a clear requirement that any equipment that has exposed, noncurrent-carrying metal parts that may become energized because of any condition shall be grounded. In this requirement, it is clear that during a fault condition this grounding means must be capable of reliably conducting the ground fault current back to the source of electrical power to activate or trip the electrical circuit protective device. To further clarify, if the equipment is not electrically powered and the metal parts associated with that equipment become energized
due to no association with electrically operated equipment, controls, devices, or lighting, then the requirement for approved current carrying conductors, lugs, terminals, etc. should not apply.

Operators, as well as contractors, are advised to review your facilities in comparison with these best practices and guidelines.

A Safety Alert is a tool to inform the offshore oil and gas industry of the circumstances surrounding an accident or a near miss. It also contains recommendations that should help prevent the recurrence of such an incident.

To Acknowledge reading please leave a comment about Grounding, or incidents or circumstances that you have heard of.

Injury Type: Crush injury to leg
Core Activity: Heavy equipment, machinery, or parts sales, rental, service, or repair (greater than 500 pounds)
Location: Northern B.C.
Date of Incident: 2016-Mar	ID Number: 2016136020002
A young worker was drilling a metal plate when the drill bit snagged the plate. The plate rotated and struck the worker’s leg.