Final answer:
Job-built trench boxes can be used in construction if they are designed according to OSHA standards by a registered professional engineer. They must ensure worker safety by adhering to specific material, construction, and load requirements.
Step-by-step explanation:
The statement that job-built trench boxes are never allowed in construction is inaccurate. While pre-manufactured trench boxes are commonly used due to their compliance with safety standards and regulations, job-built trench boxes can be used if they are constructed in accordance with Occupational Safety and Health Administration (OSHA) standards. OSHA allows for job-built trench boxes, provided they are designed by a registered professional engineer who determines they are safe for the intended use and compliant with OSHA requirements.
In construction, trench safety is highly prioritized to prevent cave-ins and related accidents. Regardless of whether a trench box is job-built or pre-manufactured, it must meet specific requirements to ensure worker safety. These standards may involve the use of proper materials, construction techniques, and adherence to load calculations and soil analyses.