Yara said..frant said..
Pretty simple. Cat 1 or Cat 2 if limited coastal. Most important is crew qualifications, again use Cat1 or 2 as guide.
Unfortunately that will probably knock 90% of the 3ksb's from here out.
KSB- well known German pump manufacturer. 3 ksb's ????
google says:
PDB id:
3ksb 
LinksPDBeRCSBMMDBJenaLibOCAPDBWikiProteopediaCATHSCOPFSSPHSSPPDBSWSPQSProSATEDSWhatcheck

Name:

Isomerase/DNA
Title: 
Detailed structural insight into the DNA cleavage complex of topoisomerases (re-sealed form)
Structure: 
DNA topoisomerase 4 subunit a. Chain: a, b. Fragment: residues 1-488. Synonym: parc55, topoisomerase iv subunit a. Engineered: yes. DNA topoisomerase 4 subunit b. Chain: c, d. Fragment: residues 404-647. Synonym: pare30, topoisomerase iv subunit b.
Source: 
Streptococcus pneumoniae. Organism_taxid: 1313. Strain: 7785. Gene: parc. Expressed in: escherichia coli. Expression_system_taxid: 562. Gene: pare. Synthetic: yes. Synthetic: yes
Resolution: 
3.50Å
R-factor: 0.186
R-free: 0.226
Authors: 
I.Laponogov,X.-S.Pan,D.A.Veselkov,K.E.Mcauley,L.M.Fisher, M.R.Sanderson
Key ref: 
I.Laponogov et al. (2010). Structural basis of gate-DNA breakage and resealing by type II topoisomerases.
PLoS One,
5, e11338.
PubMed id:
20596531
Date: 
21-Nov-09
Release date: 05-May-10
But I'm not sure that's what Frant meant