What if some new firefighting appliances were added, do we have to add the symbols on the fire plan or the class will issue a new plan? What if some symbols got scratched or damaged, can we repair it on our own?

Classification society does not issue any plan, they just approve it or endorse it. So if there is any change in the fire plan, it is the duty of the shipowners (and master) to present the new fire plan to the classification society for approval and endorsement.

Now the question is how to amend the fire plan?

Ideally, we should use mini symbols stickers to update the fire plan. These stickers are available and supplied by many suppliers such as Everlux Maritime and marine sign solutions.

Once the fire plan has been updated with these mini stickers and quantity of the fire fighting equipments updated in the fire plan, this updated fire plan can be presented to the class surveyor.

He will then stamp and initial at each location of the fire plan where these changes are made. We must make sure that all the copies of fire plan are updated and endorsed by the classification society surveyor.

Any copy that has not been updated must be updated and kept at a safer place for endorsement by a class surveyor during his next visit.

Now, what if you do not have these mini stickers. I have seen makeshift arrangements of downloading the IMO symbols and taking the color printout of these symbols and using these to amend the fire plan. 

This is acceptable provided that the print is clear and only IMO symbol is used on the fire plan. However, it is strongly recommended to use the mini stickers to amend the fire plan.

Coming to second part of the question. If some symbols got scratched or damaged, can we repair it on our own?

Absolutely. We can. But we must have at least one approved fire plan to prove that the pasted symbol is not an amendment but a repair work. It is a good practice to get these repair work also endorsed by the class surveyor whenever he/she boards the ship for any other survey.

They are happy to endorse these changes or repair works on fire plan (and they do not charge shipowners for these endorsements if done during their usual visit to the ship). 

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What to do if Fire Plan is damaged? How can we request for a new copy?