How do you calculate an installation bottleneck risk score?

Multiply the severity score by the occurrence score by the detection score. With a severity of 6, occurrence of 4 and detection of 3 the risk priority number is 4.55 on the calculator's normalized scale, which you then compare against your other crane-installation risks.

What is a good installation bottleneck score for a crane erection?

Lower is better because it means the risk is minor, rare and easy to catch before it stops work. There is no universal threshold — set a project action line (for example, flag anything in the top quartile of your scored risks) rather than chasing an absolute number.

Why multiply the three scores instead of adding them?

Multiplication makes a risk that is severe AND frequent AND hard to detect explode in value, which is exactly the crane-erection constraint you want surfaced first. Addition would let a single high factor be diluted by two low ones.

What counts as a bottleneck during terminal equipment installation?

Any step that gates the critical path — boom raising waiting on a mobile crane window, rail-gauge alignment failing survey, PLC or drive commissioning throwing faults, or SIL-rated load testing being rescheduled. Score each and rank them.

Severity vs occurrence vs detection — what is the difference?

Severity is how bad the schedule and safety impact is if it happens, occurrence is how likely it is on this build, and detection is how hard it is to catch early (a high detection score means it hides until it hurts).

How often should I re-score installation bottlenecks?

Re-score at each commissioning milestone and after any incident, because occurrence and detection change fast as subsystems come online and as you learn the site's real conditions.

Port, Crane & Terminal Equipment calculator

Installation Bottleneck Calculator

The Installation Bottleneck score is an FMEA-style risk index applied to the erection, assembly and commissioning phases of ship-to-shore cranes, RTGs, RMGs and terminal handling equipment. Site engineers and installation project managers use it to rank which steps in a crane build-up sequence — boom hoisting, rail alignment, PLC commissioning, load testing — most threaten the go-live date. It matters because a stalled crane erection ties up mobile cranes, riggers and berth window at a cost of tens of thousands of dollars per day, so the highest-scoring bottleneck deserves the mitigation budget first. Multiplying severity, occurrence and detection produces one comparable number across every installation risk on the project.

What this calculator does

Estimate installation bottleneck for port, crane and terminal equipment using production-ready inputs so teams can rank risks and decide which issue needs containment, controls, or escalation first.
Use it when installation bottleneck in port, crane and terminal equipment needs a defensible ranking against other port, crane and terminal equipment risks for the next review.
It multiplies severity, occurrence and detection scores for a single crane-installation risk into one risk priority number so bottlenecks can be ranked.

Formula used

Installation bottleneck risk score = installation bottleneck severity score × installation bottleneck occurrence score × installation bottleneck detection score
Use the same scoring scale across comparable installation bottleneck risks.

Inputs explained

Installation bottleneck severity score:
Installation bottleneck occurrence score:
Installation bottleneck detection score:

How to use the result

Use it during installation planning and daily commissioning stand-ups to decide which erection or commissioning risk gets mitigation attention before it stalls the berth window.
The score is only as consistent as the scoring scale; if severity, occurrence and detection are rated on different anchors across risks, the rankings become meaningless.

Current U.S. benchmarks

U.S. housing starts run at 1,177k per year (Census, May 2026), down 8.7% from a year earlier, the demand driver for building products.
Steel mill PPI stands at 348.53 (BLS, May 2026), up 6.7% from a year earlier. New factory orders are up 2.3% year over year (Census).

Common questions

How do you calculate an installation bottleneck risk score? Multiply the severity score by the occurrence score by the detection score. With a severity of 6, occurrence of 4 and detection of 3 the risk priority number is 4.55 on the calculator's normalized scale, which you then compare against your other crane-installation risks.
What is a good installation bottleneck score for a crane erection? Lower is better because it means the risk is minor, rare and easy to catch before it stops work. There is no universal threshold — set a project action line (for example, flag anything in the top quartile of your scored risks) rather than chasing an absolute number.
Why multiply the three scores instead of adding them? Multiplication makes a risk that is severe AND frequent AND hard to detect explode in value, which is exactly the crane-erection constraint you want surfaced first. Addition would let a single high factor be diluted by two low ones.
What counts as a bottleneck during terminal equipment installation? Any step that gates the critical path — boom raising waiting on a mobile crane window, rail-gauge alignment failing survey, PLC or drive commissioning throwing faults, or SIL-rated load testing being rescheduled. Score each and rank them.
Severity vs occurrence vs detection — what is the difference? Severity is how bad the schedule and safety impact is if it happens, occurrence is how likely it is on this build, and detection is how hard it is to catch early (a high detection score means it hides until it hurts).

Last reviewed 2026-05-12.