INTERNATIONAL CODE OF QUARANTINE SIGNALS

The following Signals are to be shown on arrival by Ships requiring or required to show the state of Health;
By Day;
a)    Q flag – Signifying ‘My Ship is Healthy and requires Free pratique’.
b)    QQ flag – Q flag over first substitute
              - Signifying ‘My Ship is suspect i. e. I have had case of quarantinable diseases
                 more than five (5) days ago or there has been unusual mortality among the
                 Rats on board’.
c)    QL flag – Q flag over L flag,
                 -Signifying ‘My Ship is infected i. e. I have had cases of quarantinable    diseases                    less than five (5) days ago’. 
  
By Night;
Red Light over a White light signifying, I have not received Free pratique’
Explanations on Flags;
a)    The Q flag is complete Yellow colour.

                        







                        


b)    The L flag is of Yellow and Black squares.










Procedures when a Ship is entering the Port;
a)    Maritime Declaration of Health form to be delivered to the Competent Authority by the Master of a Ship.
b)    Radio Pratique to be applied by Master of the Ship not more than 12 hours and not less than 4 hours before expected arrival by wireless message.
c)    Quarantine or Pratique signals must be clearly displayed which include Q flag, QQ flag, QL flag and Red Light over White Light.
d)    Granting Free Pratique to the Master of the Ship.
e)    Boarding and inspecting the Ship by Competent Authority and issuing Ship Sanitation Certificates.
Quarantine messages;
i.    ZS – My Ship is healthy and requires Free Pratique.
ii.    ZU – My Maritime declaration of Health has a positive answer to questions 1-9.
iii.    ZT – My Maritime Declaration of Health has negative answers to all 9 questions.
iv.    ZV – I believe I have been in an infected area during the last 30 days
v.    ZW – I require Port Medical Officer.
vi.    ZY – You have Pratique.
vii.    ZZ – You should proceed to anchorage for health clearance.
viii.    ZX – You should make the appropriate Pratique signals.