Analysis of MARPOL implementation based on port state control statistics

ABSTRACT This research paper deals in three main sections. The first one is a brief overview of the International Convention for the Prevention of Pollution from Ships (MARPOL), its annexes, and regulations, followed by section two with a brief overview of the Port State Control (PSC), and lastly, the third section deals with the interpretation of data extracted from the annual reports of the Memorandum of Understandings (MoUs) to assess the effectiveness of MARPOL. An analysis of MARPOL related deficiencies from all nine MoU has been designed. The annual reports for the past 11 years have been extracted and data relating to total inspections, total deficiencies, and deficiencies with regard to the MARPOL convention, distinguished as per annexes has been extracted and analysed using statistical tools to find out the level of implementation of the code. The extracted data has been categorized to find out the trend of the MARPOL-related deficiencies through the years and to find the annexes of MARPOL with most common and least common non-conformity.


Background
The maritime industry has always been internationally acclaimed, now it has turned global. Maritime transport has been at the forefront of globalism, with the consequent intimidations for capital, working-class, and the environment (aaa 2014). With the growing rate of the shipping business and the growing number of ships on the high seas has subsequently placed the marine environment at great danger due to the increase in the amount of garbage and excretions from ships, accidental or operational. One of the fundamental environmental issues faced today is the pollution of the world's oceans from ships.
In the past, the mammoth concern has been the dumping or accidental discharge of bilges containing oily water mixture, anyhow, in today's scenario, we face extensive dread for the impact on marine ecosystems of vessels generated garbage, sewage and other wastewater, and residues from cargo dumped at sea (Dissertation To Ngoc Thang 2015). Vessels continue to discharge waste at sea despite wide-ranging legislation at the national as well as the international levels, maybe it seems to be the most convenient and costeffective method when it comes to disposing of unwanted matter, it may also be of a viewpoint that the garbage will degrade eventually. However, vessels typically generate a variety of throwaways, which includes organic waste, plastic, paper, glass, metal, and hazardous waste. Items like food waste and paper are degradable faster; whereas there are other items which may take months or years, for example, plastic bottles may take approximately 450 years to biodegrade as per the research data of the Hellenic Marine Environment Protection Association (Dissertation To Ngoc Thang 2015; Dissertation Nguyen, Thanh Hoang 2017).
The accident of the vessel Torrey Canyon in 1967, which ran aground and released approximately 12,000 tonnes of crude oil into the sea, raised questions and exposed the shortcomings of the then existing instrument for combating the oil polluting, i.e., the OILPOL (International Convention for the Prevention of Pollution of the Sea by Oil) adopted in 1954. As a result from this accident and to encounter any such predicaments in the future, the IMO adopted a detailed international instrument as a part of the maritime law to deal with the accidental as well as operational pollution of the sea and the environment i.e., The international Convention for the Prevention of Pollution from Ships (MARPOL 1973), as modified by the protocol of 1978, known as MARPOL 73/78 and is updated by amendments through the years. Sufficient number of states ratified the convention in 1982 and it entered into force on the 2 October 1983. The Convention focuses on regulations to prevent and reduce pollution caused by oil, chemical, harmful substances, sewage, garbage, and emissions from ships (Dissertation Nguyen, Thanh Hoang 2017).
The P&I Clubs usually covers all vessel which are under insurance for pollution related expenses in case of an accident (e.g., to clean up for preventing and/or minimizing pollution and other liabilities), whereas, its noteworthy that the P & I clubs doesn't recover any fines arising from the violation of MARPOL.
While complying with the MARPOL, the following are of paramount significance-• All vessels are required to hold all original certificates onboard issued by flag states or RO, as required by the convention, stating the vessels compliance to various regulations of MARPOL. • Sanctioning of MARPOL violation must be under the state's law under whose flag the vessel is flying, irrespective of geographical location of the infringement. • A vessel's Master is responsible to keep all certificates onboard and bring to the notice of appropriate department in case of renewal or issuance of certificates, he should also be held responsible to make and submit reports in case of incident.

The annexes
Each annex of MARPOL sets out specific requirements with regard to various types of pollutants covered for vessels. The convention is divided into six annexes to facilitate combating different kinds of pollution and prerequisites for vessels. Table 1 shows the different annexes along with details pertaining to the annexes. Annex I lays down detailed regulations to deal with the measures of prevention of pollution by oil including regulation on as basic as definitions of oil, sludge, tanks, etc. It stated that the rules apply to all vessels, unless specified otherwise. Exemptions have been granted to discharge oil into the sea in lieu of situations where it's done to secure the safety of the vessel or to save life at sea, discharge is case of damage to the vessel or its machinery or discharge while combating specific pollution incidents to minimize the damage from pollution, approved by the administration. Requirements related to surveys and certification is detailed in regulations 6 through 10. Any discharge is permitted outside special areas and arctic waters, if the vessel is en route; the mixture is processed through an oil filtering equipment in accordance with regulations and the oil content of the effluent without dilution does not exceed 15 ppm. In case of tankers, not originated from cargo pump room bilges and not mixed with oil cargo residues.
Details on segregated ballast tanks, oil tanks, double hull, double bottom, specifications of cargo tanks, slop tanks, discharge manifold for connection to reception facilities, piping, and pumping for discharge into the sea are laid down as per vessels type and size in Part A of chapter 4. The specification of equipment for controlling and monitoring oil discharge, oil/ water interface detector, requirements for crude oil washing is dealt in Part B. Chapter 5 deals with the requirement of carrying a Shipboard Oil Pollution Emergency plan (SOPEP). The requisites of a reception facility, capacity, and strategic locations where they must be provided, within and outside special areas, are covered in chapter 6.
Chapters 8 through 11 contain regulations on STS operations, requirements on Antarctic region oil usage and carriage, compliance verification and the code for polar water operations.
Annex II regulates Noxious Liquid Substances (NLS) in bulk applies to all vessels certified to carry NLS in bulk, unless specified otherwise in any specific regulation. Exceptions for discharging NLS into the sea are same as laid down for Annex I. Exemption relating to constructional and operational features and alternatives of material or equipment are discussed in regulation 4 and 5. NLS are categorized into four types. The substances are differentiated on the basis of evaluation of their properties in the resultant GESAMP hazard profile. Table 2 shows the differentiation.
Chapter 3, comprising from regulations 7 to 10, provides insight on surveys and certification requirements of NLS carriers. The operational requirements and vessel constructions of the NLS carriers shall be in conformance with the chapter 17 of the International Bulk Chemical Code (IBCC). Table 3 shows the requirement of pumping and piping equipment for each tank of NLS carriers with permitted amount of residue in the tanks and associated piping. Whenever discharge of substances under category X, Y or Z, ballast water, or mixtures containing such substances is permitted in accordance with this Annex, the vessel must be en route with a speed of at least 7 knots for self-propelled ships and 4 knots for others, underwater discharge outlets must be used, and at a distance of more than 12 miles and depth over 25 meters. Discharge of any mixture containing NLS is prohibited in the Antarctic.
A manual with operational procedures of the NLS carriers in compliance with the Annex must be present onboard. A cargo record book has also been specified mandatory for such vessels. Chapter 7 requires all NLS carriers of over 150 t GT to carry onboard a Shipboard Marine Pollution Emergency Plan for NLS.
The provisions of adequate reception facilities at the cargo handling terminals and repair ports are covered in chapter 8. Compliance verification and polar water operation code are detailed in chapters 9 and 10.
Annex III regulations are applicable to all vessel carrying harmful substances in packed form, unless specified otherwise. The carriage of harmful substances is permitted only when acted in compliance of this annex, except for ship stores and equipment. It is also emphasized that empty packaging used to carry harmful substance must also be treated as harmful unless it's clear that no residue is present that can harm the environment. With regard to the content, adequate packing should be provided to minimize the hazard should be marked and labelled in accordance with the IMDG code.
These substances must be properly stowed, in accordance with a stowage plan showing locations of the harmful substances and a manifest of the same must be prepared in accordance of the IMDG code and circulated to all relevant parties involved. Limitation of carriage of substances, when applicable, must be exercised considering vessels specifications.
These substances may only be jettisoned to secure the safety of the vessel or to save life at sea. Chapter 2 of the annex deals with the compliance verification.
Annex IV regulation applies to all vessel above 400 t GT and vessels certified to carry more than 15 persons engaged in international voyages. Discharge of sewage is exempted for securing the safety of the vessel, saving life at sea or resulting from damage to ship or its equipment provided that reasonable precautions are taken at all times. Chapter 2 deals with the requirements of survey and issuance of certificates in relation to the Annex.
Every vessel to which the Annex is applicable shall be equipped with an approved sewage treatment plant, or a sewage comminuting and disinfecting system, or an administration approved holding tank A connection for discharge piping of standard specification must be available to connect to reception facilities, the specification of the flanges and bolts are present in regulation 10, alternatives may be accepted by the administration for vessels in dedicated trades.
Sewage from all vessels, except passenger vessels in special area may be discharged if it is comminuted and disinfected at over 3 miles from nearest land and over 12 miles when it is not comminuted and disinfected, provided when using holding tanks, that its discharged when vessel is en route and at a speed of minimum 4 knots, or the vessel uses an approved sewage treatment plant. Sewage discharge from passenger vessels in special areas is prohibited except when an approved and certified sewage treatment plant is operational.
The parties to the convention have the obligation to provide adequate reception facilities at operational as well as repair terminal to receive sewage from vessels without any unnecessary delay. Compliance verification and polar water operation code are detailed in chapters 6 and 7 respectively.
Annex V regulates the garbage prevention of pollution from ship-generated garbage; regulations of this Annex are applicable to all vessels unless expressly stated otherwise. The acceptable discharge of garbage outside special areas is comminuted or grinded food waste, capable of passing through a 25 mm opening screen at over 3 miles from nearest land, 12 miles otherwise. Non harmful cargo residue which cannot be recovered using common unloading methods may be discharged at 12 miles from nearest land. Animal carcasses may be dumped at sea, provided it's done as far as practicable from the nearest land, as per the guidelines.
Garbage discharges from any kind of platforms or vessels alongside or at 500 m radius are prohibited. Only comminuted or grinded food waste capable of passing through a 25 mm opening screen is allowed to be discharged by platforms and vessels around it if the platform is located at more than 12 miles from the nearest land. In special areas, food waste that has not been contaminated by any other garbage type and comminuted or grinded, capable of passing through a 25 mm opening screen is allowed to be discharged at 12 miles or more from nearest land or ice shelf. Antarctic areas prohibit discharge of avian products, including poultry, unless made sterile. Conditions for discharge of cargo residue in special areas are detailed in regulation 6.
Governments of parties are liable to provide adequate reception facilities for discharge of garbage at terminals without causing undue delay to the vessels.
Garbage discharge requirements in accordance with this Annex must be posted via placards in appropriate languages on all vessels of length 12 m or more. A garbage management plan based on appropriate guidelines with procedures for garbage related activities and use of equipment onboard must be provided to all vessels above 100 t GT, vessel certified to carry 15 or more persons and all platforms. A garbage record book must be provided to every vessel of 400 t GT, vessel certified to carry 15 or more persons and all platforms. Entries to be made in the record book are mentioned in regulation 10.3. Compliance verification and polar water operation code are detailed in chapters 2 and 3 respectively.
Annex VI regulates the Air pollution prevention from ships. Regulations of this Annex are applicable to all vessels unless expressly stated otherwise. Emissions are exempted for securing the safety of the vessel, saving life at sea or resulting from unintentional damage to ship or its equipment provided that reasonable precautions are taken at all times. Exemptions are also made for emissions with regard to exploring, exploiting and processing seabed mineral resources. Chapter 2 deals with the requirements of survey and issuance of IAPP, IECC, and statement of compliance related to fuel oil consumption certificates in relation to the Annex.
Deliberate emissions of Ozone Depleting Substances (ODS) from a system or equipment occurring in the course of maintaining, servicing, repairing or disposing are prohibited.
Installations containing ODS, other than Hydrochlorofluorocarbons (HCFC's) shall be prohibited on vessels constructed on or after 19 May 2005, and Installation containing HCFC's shall be prohibited on vessels constructed on or after 1 January 2020.
Every vessel must maintain a list of ODS containing equipment and maintain ODS record book if rechargeable systems containing ODS are present onboard. Any such equipment or ODS, when removed from the vessel, must be delivered to a reception facility. The regulation with regard to emission of Nitrogen Oxides (NOx) applies to marine diesel engines installed onboard with over 130 kW power output or an engine with same specification but has undergone major conversion on or after 1 January 2000. The regulation does not apply to lifeboat engines, a marine diesel engine used directly or to power any other equipment, with an intention to be utilized only for emergencies, or a vessel engaged in voyages only in the jurisdiction of the flag state, provided alternate measures are taken by the administration.
The sulphur content of fuel oil used in marine diesel engines onboard must not exceed 0.50 % m/ m on or after 1 January 2020, and 0.10 % m/m on or after 1 January 2015 in Emission Control Area. If emissions on volatile Organic Compounds (VOC) from tanker are to be regulated; it should be in accordance of Regulation 15 of this Annex. Provisions regarding shipboard incineration are provided in regulation 16. Incineration of cargo residues with regard to substances covered in Annex I, II, III, polychlorinated biphenyls (PCBs), garbage with more than traces of heavy metal, sewage sludge and sludge oil, petroleum products containing halogen compounds and residues from exhaust gas cleaning system is prohibited. Fuel oil quality requirements are given in regulation 18. Chapter 4 deals with the energy efficiency on ships, which applies to all vessels above 400 t GT. Exemptions are made for vessels engaged in voyages only in the jurisdiction of the flag state, provided alternate measures are taken by the administration and for ships not using mechanical means of propulsion and platforms.
Every vessel must have a Ship Energy Efficiency Management Plan (SEEMP) specific to each vessel. The energy efficiency of a vessel can be estimated by calculating the attained Energy efficiency Design Index (EEDI). The process of calculation and information required for calculating must be accompanied in an EEDI technical file onboard.
Attained EEDI ≤ Required EEDI = (1-X/100) x reference line value Where "X" is the reduction factor, values for same are specified in regulation 21.2 The calculation of the reference line value is also specified clearly in regulation 21.3. Chapter 5 deals with the compliance verification.

Implementation
Referred from Table 1, it's clear that the convention has application globally. Nguyen Hoang Thang (2017) states that "Ratification and implementation of international treaties related to marine environmental protection, safety, and security aspects are one of the best solutions to overcome marine pollution (Dissertation Nguyen, Thanh Hoang 2017)," but when it comes to implementation, it gets tricky. Firstly, the ample high seas with no jurisdiction or ways of monitoring gives the vessels involved in illegal dumping great scope to carry out their illicit activities. Secondly, in case of any evidence of violation, MARPOL does not give the power to a state to take direct action against such violations; the state is expected to report the same to the flag state of the vessel (MARPOL, Art III (3)). The flag state then have the liability to investigate and take appropriate actions accordingly. Here, the flag of convenience (FOC), using this loophole to increase their business, might delays investigation or completely turn a blind eye towards such violations from vessels flying their flag. For ship-owners the FOC provides many alluring benefits, one of which is slack on expenditure related to environmental standards (Akpama and Ofem 2017). Thirdly, the provision and utilization of the reception facilities in terminals are of utmost significance in achieving the MARPOL's goal of eradicating pollution of the oceans from the shipping industry, as far as practicable. For this objective to come true there is need to provide mariners with means of disposing waste from ships. According to MARPOL Annexes, the terminal's reception facilities must be adequate, according to the traffic density at the terminal, and operate without causing unnecessary delays to the vessels (Online document, MEPC. iicirc. 671, 2009). But, the provision of waste reception facilities at terminals is still an issue at many ports even after decades of implementation of the convention. In my personal experience in 2017, was a declined port reception facility at a Malaysian port after a voyage of five days; same has been a case in a port of Indonesia as well in 2013.
Flag States and the recognised organisation, for e.g., classification societies play the most significant factor in making the vessel-owners complying with international regulations. The concerned authorities must carry out surveys to make sure that the prerequisites of the conventions are complies with. The vessel owners and operators ultimately hold the responsibility for the seaworthiness of their vessels. They are the one who needs to step up and make sure that their vessels and the equipment onboard are always in compliance with the codes and conventions of the IMO because the flag states only inspects the vessels once a year and its very likely that the vessel transits in local regions or regions where port state is not strict, in this case the vessels seaworthiness and compliance to regulations totally depends on the owners mindset towards the safety of the crew and environment. As the gist of the business is to make money, and compliance to regulations required spending of funds, a lot of ship-owners, who are not forced to comply, chooses to turn a blind eye until next inspection, causing substandard ships to ply the oceans.

MEMORANDUM OF UNDERSTANDING ON PORT STATE CONTROL
PSC is an inspection regime to eradicate substandard shipping, the flag state of a vessel is primarily responsible for making sure that a vessel under their flag is seaworthy and complies with the provisions of all international conventions. If the flag states carry out their jobs flawlessly, there isn't a need of PSC at all, but in the real world, that isn't the case. Of course, there are many sub standard ships on the sea, posing danger to life, property and the environment. PSC acts as a safety net to catch these sub standard ships and make the shipping industry safer for all parties involved. Then again, there are millions of ships, hundreds of them berthing and un-berthing at a given day on each port, the inevitable question arises, how can we inspect all these ships. Even if we could, how much time will it consume and cause tremendous delay to the vessels.
The PSC inspections differ from that conducted by flag States or RO. The surveyors of the latter indulge in surveys to issue the statutory certificates for a vessel, which might be done at a rendezvous port and time finalised by the vessel owner's and surveyors consent. On the other hand, the PSC is forced to complete its inspection in the time the vessel is berthed at the port, without causing unnecessary delay to the vessel. Another prime difference is that the flag state's inspections are at owner's request, whereas PSC inspections are not a requirement for the owners to run their vessels, but a catalyst to motivate owners to keep their vessels deficiency free.
Some vessels today faces detention for trivial non conformities, this may be caused due to the lack of judgment on the part of PSC officers. For the PSC to be bloom further, its resources should be unanimously focused below par ships, in such a way that it would be unsustainable for below standard ships and their operators.
The Paris and Tokyo MOU, with a far superior administration with respect to other MoU's was able to achieve better cooperation and synchronisation of members and data exchange within areas covered under their jurisdiction which cannot be said for other MoU's Efficient PSC involuntarily forces the vessel operators to uphold the standards of their vessels because if not, there is always the dread of their vessel's detention lurking. It also assists to encourage the safety of life at sea, property, and the environment, and achieves its primary objective to seize below standard non-compliant vessels.
In its wake, it also exposes certain flag states which render unsuccessful in implementing required standards as per the IMO, and forces such vessels to ports in regions where the PSC inspections are less frequent or less vigorous. The overall objective of PSC will take a hit if these unscrupulous keep transiting in other parts of the world, so it is of significance that all the regional MoU's have a solid administrations and  resources to carry out their job effectively and efficiently.
Most of the resources we have at our disposal are limited, PSC inspectors are the same. They can only inspect a limited number of ships at a given time and this gives scope to sub standard ship to continue causing harm to life, capital and environment. To tackle these problems, the IMO adopted Resolution A.682 (17) on regional cooperation to promote regional agreements on control of vessels. Regional Memorandum of Understanding (MoU) were formed to achieve harmonization of PSC surveys, backed by IMO in resolutions A.787 (19) as amended in resolution A.882 (21) (DOIYuan, Chiu, and Cai 2020). Hence, it can be concluded that the PSC acts to put a check on unseaworthy vessels transiting the high seas, and to make sure that entering ports in their region are complying with the international regulation set forth by the IMO under various codes and conventions.
At present, the following nine MOUs cover virtually all seas of the world:

Interpretation of data from annual reports of all nine MoU's
An analysis of all nine MoUs were carried out based on the number of member states and the number of deficiencies reported by them, Abuja MoU and the Caribbean MoU were found to have comparatively very less number of MARPOL deficiencies, but to maintain an higher accuracy of the data interpreted, both these MoUs were also taken into consideration for analysis. Mar 2021). These annual reports provide a vivid description of all the inspections carried out, detentions, deficiencies reported amongst others. The reports also distinguish between the types of vessels inspected, flags, member states and classification societies. A differentiation based on the type of deficiencies is also reported, for the purpose of this analysis, the deficiencies related to all annexes of MARPOL and related to operational deficiencies of MARPOL for the years 2009-2019 are extracted and interpolated to achieve the result of the analysis. Data on number of inspections and total number of deficiencies have also been extrapolated for the same period for analysis.
The following variables have been used for analysis; total number of inspections, total deficiencies, annually reported MARPOL deficiencies, Annex I, II, III, IV, V, VI deficiencies, percentage of MARPOL related deficiencies.

Results
The  The inspection numbers of MoU's other than Paris and Tokyo MOU's are comparatively very low. More distinctly, Caribbean, Abuja and Riyadh MoU's record of inspections are on the lower side with just 782, 2695 and 3207 inspections respectively. Another noteworthy point is that the inspections of all the MoU's are fairly consistent, which can lead to an assumption that not much efforts have been made to increase the frequency of the inspections by MoU's with very low numbers. Figure 2 depicts the number of deficiencies reported by each of the nine MoU's as a result of inspections carried out under Figure 1. Six of the nine MoU's have registered a decline in the number of deficiencies, in spite of an average increase in the number of inspection carried out, which can in fact be interpreted as increase in compliance with the international instruments and maritime law. Riyadh, Abuja and Caribbean MoU has recorded an spike in the number of deficiencies in comparison to 2009, but its noteworthy that all three of these MoU's have very low rate of inspections and deficiencies to start with in 2009, and numbers have not relatively increased in the 11 years period.

Assessment related to inspections and deficiencies
In terms of percentage, Acuerdo Viña del Mar and Mediterranean MoU's registered a decline in deficiencies of over fifty percent, 77.5 % and 60.5 % respectively. Others registering decline are the Paris MoU (44.5 %), Indian Ocean (37%), Tokyo MoU (15.5 %) and Black Sea MoU (15.1 %).
Even though the Riyadh, Abuja and Caribbean MoU's has the least recorded number of deficiencies, but these MoU's has seen an increase in the numbers. Riyadh MoU has specifically seen an exceptional spike of 192 % since 2012 in terms of percentage, but the number of deficiencies are just 2713 in 2019, whereas Caribbean and Abuja MoU's has recorded an increment of 79 % and 5.2 % respectively.

MARPOL related deficiencies
The number of deficiencies reported by each MoU for the periods 2009-2019 has been extracted from the annual reports and tabulated in Table 4, differentiated by the deficiencies reported per annex, per year and per MoU. Referring to Table 4, Riyadh and Abuja MoU's have not reported MARPOL related deficiencies separately from 2009-2011, whereas Mediterranean MoU has furnished cumulative data related to MARPOL deficiencies but has not differentiated the deficiencies on the basis of annexes.
The number of deficiencies reported each year is depicted as the percentage of total deficiencies in Figures 3 and 4. To reduce the clumsiness and for the ease of understanding, the data is interpreted in two figures instead of one. Figure 3 shows the data for Indian, Riyadh, Tokyo, Black Sea and Acuerdo Viña del Mar MoU's, whereas Caribbean, Paris, Abuja and Mediterranean MoU data is shown in Figure 4. The Paris and Mediterranean MoU registered and reduction in MARPOL deficiencies by 22.1% and 66.5% respectively, whereas the Caribbean and Abuja MoU's recorded an increment of 117.2% and 63.6% respectively.

MEDITERRANEAN MoU
The results are fascinating as almost half of the deficiencies (41.9 %) are attributed to annex I of MARPOL, the numbers are high for annex I not just because it is the oldest one but also due to its widespread applicability, and the recent years have also seen the numbers high on Annex I's side. So, it's evident that tackling vessel's and equipment's non compliance on Annex I will reduce the MARPOL related deficiencies by a great deal.
Annex V follows next with a share of 22.07%, followed by annex IV and VI with 14.64% and 11.54% respectively, whereas annex II and III just attributed to 0.64% and 0.38% respectively.
2.39% of deficiencies are related to operational deficiencies and uncategorised deficiencies add up to 6.43%. Trend of MARPOL deficiencies anually   I reckon that deficiencies related to annex VI of MARPOL would soon see a spike in the recent future as the sulphur cap requirements (maximum limit of sulphur in the vessel's fuel oil) have entered into force on 1 January 2020. Because of the lack of data for the same, the new regulation's effects on deficiencies caused at PSC inspections are yet to be determined.

CONCLUSION
The mankind pivots around the oceans, not just for the transportation but with over 70% of oxygen generated in the oceans and for its ecological effects, the oceans are of utmost importance. Now, the oceans are constantly polluted by land based facilities and the ships every day, changing the ecology and habitat of many sea creatures and in turn affecting human kind in the long run.
The oceans are being polluted by various sources, amongst which, a significant hand is also played by the vessels transiting the oceans for transportation. As the maritime industry is involved in pollutions, it's also obligated to clean up after itself. To tackle the marine pollution from vessels, the IMO and the local authorities has in place various conventions and legislations, but all the preparations to tackle a problem in the ends depends on the level of implementation. With vessels transiting in the high seas, away from prying eyes, it's difficult to keep such unscrupulous activities in check. Nevertheless, there are ways to see the compliance of vessels to convention directed to reduce the pollution of natural resources.
Before conducting this research, with the sea experience I have and all I have witnessed at the high seas hypothesised that there is a lot of non compliance in regard to MARPOL and its annexes.
The PSC is of course one of the primary instruments to conclude the marine sector's compliance with the necessary conventions. The data extracted from the annual reports of all the MoU's has pitched against the author's hypothesis and an overall reducing trend of deficiencies has been found in the analysis. This could either direct that the marine industry has indeed succeeded in combating the pollution or the vessel operators have found a way around PSC inspections.
I would have concluded that we are moving towards a trend of reducing the pollution as prescribed in MARPOL, if the data from all the MoU's were consistent. But areas under MoU's like Abuja and Riyadh have reported very less number of MARPOL-related deficiencies, just 36 and 187 MARPOL related deficiencies for Abuja and Riyadh MoU's respectively for the year 2019. It's evident that both these regions are not conducting enough inspections and the inspections being conducted are vigorous enough.
The PSC inspections need to step up a notch in regard to MARPOL compliance to make the oceans cleaner. It can anyhow be concluded from the analysis that Annex I and V are the most non compliant regions to work on for the maritime sector.
A scope for further study persists as the data from PSC also is not enough for concluding strongly in the positive direction. Seafarers are the last link to implement positive compliance of the MARPOL, an objective of this study is also to educate the seafarers of the adverse effects and the trends depicted in the marine industry regarding pollution from ships. Even if a handful of seafarers reading this paper decides not to be a part of polluting the oceans, I will consider this paper's objective met.

Disclosure statement
The author declares that he has no competing interests.

Funding
No funding was obtained for this study.

Availability of data and material
The data used are freely available on each of the MoU's websites. Only the Acuerdo Viña del mar MoU's official website was down while collecting the data, in this case data has been extracted from www.equasis.org, other sources of data is from published sources available online.

Ethics approval
No ethical approval is necessary for this study.