April 2021

Engineering and Construction

Modular construction: Always considered, now COVID-necessary

The COVID-19 pandemic created a sequence of changes across all industries, and the chemical sector has not been immune to the impact of this global health crisis.

Villegas, M., Koch Modular Process Systems

The COVID-19 pandemic created a sequence of changes across all industries, and the chemical sector has not been immune to the impact of this global health crisis. What used to be a “nice to have” feature in project execution has evolved into a “must-have” component. Although modular construction is not a new concept, it may become a necessity in current times.

Modularization is described as the process of shifting as much labor-intensive field construction activities from the field to an offsite fabrication facility to mitigate or reduce inherent risks associated with field construction.

Typically, a modular system includes complete process units that are fabricated remotely from the project’s destination plant site. The systems are built in a controlled indoor environment, assembly-line fashion horizontally as opposed to vertically, which helps minimize the amount of work and resources needed vs. field construction. The systems include all necessary components and equipment that are placed within a structural steel frame required to deliver a complete process system. These frames serve as support during shipment and provide access to the equipment for operation and maintenance after installation at the plant site.

The project’s process design, specifications, engineering standards and guidelines are all taken into consideration and followed to ensure that the executed project meets all expectations and requirements.

Key advantages of modular construction

Considering the importance of operator safety and social distancing during COVID-19, the following are five key advantages of modular construction:

  1. Reduced risk of community spread. When dealing with on-site construction, depending on the project size, fabrication may require over 1,000 craft workers to be performing different tasks simultaneously. In many cases, these are transient workers who will be newcomers to the community. Adding more people to an area can increase the risk of human-human exposure or could promote the spread of COVID-19 to other areas as the transient workers return home due to crew rotations.
  2. Reduced risk of exposure to the labor force. Modular assembly typically follows a preset sequence of activities that inherently require a smaller local workforce. This allows for social distancing during work activities, while still being able to adhere to Occupational Safety and Health Administration’s (OSHA’s) recommended guidelines related to the prevention of workplace exposures to COVID-19. It also brings an advantage from the logistics perspective, as a small local workforce is easier to manage vs. a field-built project, while reducing the likelihood of exposure.
  3. Reduced cost and schedule risk. Traditionally, customers could see a 25%–30% cost reduction with modular construction when compared to field construction. The project can be quoted as a firm lump sum bid vs. time and materials (T&M) and fabricated to within 90% completion, with items such as piping components, field instrumentation, lighting, electrical wiring and others installed within a steel frame. All of this is done offsite, reducing the amount of onsite work required during installation. Furthermore, in parallel, the customer can proceed to apply for work permits as the construction of the modules have already begun at an offsite shop, while minimizing plant-site interruptions due to construction. During a COVID-19 environment, with fabrication occurring offsite, the ability to continue module fabrication when field construction sites would otherwise be shut down or materially impacted by COVID-19, reduces the potential for extended schedule and increased costs associated with delays. Furthermore, minimal plant site interruptions allow the customer to proceed with their normal operations, adjust to the new requirements and create a set of preventive procedures that can be later shared with the module installation workforce.
  4. Increased productivity. Building a full system in a controlled environment brings many benefits, including increased productivity. For example, the workforce is not subject to weather-related delays and benefit from inherent efficiencies when working in a purpose-built fabrication facility. Considering COVID-19, fabrication shops are not experiencing the same level of productivity hits being taken in the field during construction. In the field, construction teams are implementing preventative measures such as daily pre-work health checks, staggered lunch schedules, breaks and re-checks when the workforce members enter and exit the field construction facility to minimize risk exposure to COVID-19. These required, and necessary practices are important to protect workers from exposure. However, they come at a cost to productivity. Naturally, a smaller fabrication shop crew vs. a full field construction crew—that could be thousands of workers—minimizes the impact to productivity and eventually cost and schedule. Working in a controlled environment, which is offsite from the client, also allows for ease of maintenance of sanitized workspaces with a smaller concentration of crew members.
  1. Reduced commercial and contractual risk. Decreased productivity, schedule delays, rising project costs, among others, resulting from a COVID-19 environment, present themselves eventually as commercial and contractual risks, such as liquidated damages and a possible force majeure. By leveraging
    the inherent benefits of modularization, suppliers and owners can minimize the likelihood and/or severity of such commercial and contractual risks.

The geography of the pandemic

Unlike field construction, modularization is not geographically constrained to the plant site. If a customer’s site is in a region where there is a high risk of COVID-19 exposure, the fabrication of the modules is location independent; therefore, a fabrication site that is in a state where COVID-19 has a much lower prevalence can be selected.

In general, modular construction can ensure safer construction because the assembly area can be restricted to have as few as one or two workers in a horizontal orientation separated by much more than 6-ft. However, on larger projects, it is even possible to split the fabrication across two or more geographically separate assembly locations, minimizing the number of modules and workers present simultaneously, thus reducing the risk of project interruptions should a COVID-19 outbreak occur at one of the fabrication sites.

By applying the inherent health and safety, quality, cost and schedule benefits and leveraging them in a COVID-19 environment, owners can lower project delivery risk to manageable levels; therefore, enabling sound project go/no-go decisions. Our industry is built on projects and employing a modular project delivery model during a COVID-19 environment can be the path to successful project delivery during these times of uncertainly. Flexibility, creativity, resourcefulness and social responsibility have become key characteristics of project execution across the oil and gas and chemical industries. HP

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