1 

OSPAR Commission Summary Record OIC 2003 OIC 03/15/1-E, Annex 6 

ANNEX 6

(Ref. § 3.11)

OSPAR CONVENTION FOR THE PROTECTION OF THE MARINE ENVIRONMENT OF THE 

NORTH EAST ATLANTIC 

MEETING OF THE OFFSHORE INDUSTRY COMMITTEE (OIC) 

LONDON (SECRETARIAT): 10-14 MARCH 2003 ________________________________________________________________________________________________ 

OSPAR Guidelines for Completing 

the Harmonised Offshore Chemical Notification Format (HOCNF) 

(Reference number: 2003-1) 

Introduction 

1. The Harmonised Offshore Chemical Notification Format (HOCNF)1 applies to all chemicals used in 

connection with offshore exploration & production activities in the OSPAR maritime area. Exact chemical 

composition of preparations will be held in commercial confidence in the relevant governmental bodies, and 

will not be published or transmitted to third parties. 

Data Requirements 

2. For the purpose of these OSPAR guidelines, the following data requirements apply: 

a. "mandatory data" must always be provided; 

b. "conditional data" become mandatory when the defined conditions mentioned in Appendix 1 

of the OSPAR Recommendation 2000/5 on a Harmonised Offshore Chemical Notification 

Format (HOCNF) or in these guidelines are met; 

c. "optional data" should be provided by the supplier if available and relevant. 

3. The following text of these OSPAR guidelines relates to the provisions and requirements stipulated 

in Appendix 1 of the OSPAR Recommendation 2000/5 on a Harmonised Offshore Chemical Notification 

Format (HOCNF) and the 'parts' and 'paragraph numbers' mentioned in the headings and subheadings refer to 

that Appendix of that OSPAR Recommendation. 

PART 1: General information on substances and preparations 

§ 1.3 Use 

4. Information on quantities used and discharged and on application categories is required based on 

standardised reference installations or, where appropriate on site specific use and discharge. The function is 

defined as the process for which the substance/preparation is normally or primarily used, e.g. drilling fluid, 

biocide, scale-inhibitor, demulsifier. 

5. If the submitted chemical is suitable for assessment by CHARM, choose an application from one of 

the four main CHARM algorithms: “Cementing”, “Drilling”, “Production” or “Completion/Workover”. 

Since the CHARM model incorporates Utility and Stimulation chemicals into the combined 

“Completion/Workover” algorithm, please do not select “utilities” or “stimulation” but indicate as a footnote 

 

1

 cf. Appendix 1 of OSPAR Recommendation 2000/5 on a Harmonised Offshore Chemical Notification Format 

(HOCNF) 
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OSPAR Commission Summary Record OIC 2003 OIC 03/15/1-E, Annex 6 

whether the chemical is a stimulation or utility chemical. If the submitted product is a cementing chemical 

choose “other” and state “cementing”. 

6. If the submitted chemical is not suitable for assessment by CHARM, advice should be sought from 

authorities on what information is requested in addition to that required in the HOCNF. Such information 

may be that necessary to allow assessment by models other than CHARM. 

7. The entry sections "state function(s) of the substance/preparations" and "to which process system 

will the chemical be applied?" should confirm the function of the chemical and its mode of use. The 

function of the chemical should be taken from Appendix 2. If none of the listed functions are appropriate, 

enter the function as ’other’ and ensure that a clear written description is provided confirming mode of 

use, fate and effect. The application process stream should define the process stream into which production 

chemicals will be dosed; or list the sections of a well in which the drilling chemicals will be used; or 

should reflect one of the four CHARM sub-algorithms for cementing or completion chemicals. 

8. For water based drilling chemicals, all the well sections, in which the product is likely to be used 

should be stated. The normal dose rate should be based on optimal technical performance and the appropriate 

sections of a standard well of the CHARM model (171/2’’, 121/4’’ and 81/2’’ sections) or, where 

appropriate, on site specific information. Units should be clearly stated. 

9. For production chemicals, state either “water” or “total fluids” as the process system into which the 

chemical will be applied. “Total fluids” should be selected for chemicals dosed into single-phase 

hydrocarbon streams (either oil or gas) and the dosage should be based on the sum of the produced water and 

hydrocarbon production of the appropriate CHARM model platform. “Water” should be selected for 

injection chemicals and surfactants. State whether the production chemical is to be used on a gas or on an oil 

platform. 

10. For all cementing chemicals except spacers, “mixwater” should be stated as the process system. For 

chemicals used in spacer fluids, enter “spacer” as the function of the chemical. 

11. For completion chemicals, enter the function “surface and well cleaning” for products used as rig 

washes or “other completion/workover” for any other products used in completion and workover operations. 

12. If a product is used in several different applications, data on function, process stream dosage, 

discharges etc. Should be applied on additional pages (§1.3 and §1.4) in the same HOCNF data sheet. 

13. If the above sections have been filled in as indicated, then no more information is required to run the 

CHARM model. However, an estimation of the “frequency of treatment” and “probable scale of use” should 

be reported in this section of the HOCNF to inform site-specific risk assessment. 

§ 1.4 Discharge 

14. A substance/preparation should be assigned to the category "closed system" only if it remains within 

a reactor or is transferred from vessel to vessel through closed pipework and therefore accidental spillage is 

the only likely cause for human exposure or environmental contamination. Substances/preparations that are 

used in closed systems, but as a consequence of normal use might be released into the environment after use 

or where significant discharges into the environment cannot be excluded during use, should be assigned to 

the "open system". 

15. Data in §1.4 must be given for all offshore chemicals. 
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OSPAR Commission Summary Record OIC 2003 OIC 03/15/1-E, Annex 6 

§ 1.5 Fate 

16. A description of the likely fate of the substance/preparation can be explained in general terms.. This 

should include whether the substance/preparation is likely to change its form on use and/or will end up in the 

sediment, the water column, the air or biota. 

§ 1.6 Composition 

17. In all applications concerning chemicals used offshore, the names of all deliberately added 

substances within a preparation shall be reported to the competent national authorities. Sufficient 

information must be available to operators to allow them to properly assess the chemicals they use. 

18. When providing this form to non-governmental organisations, information regarding composition as 

normally given on a Safety Data Sheet (SDS) should be provided. 

19. The full chemical composition must be given when submitting the form to government bodies. The 

complete and precise composition of the substance or preparation should be reported, including each "active" 

substance, "inert" substance, solvent and additive substance and their proportions, using CAS numbers and 

recognised chemical formulae or recognised chemical names for all substances. 

20. Constituent substances should be named and concentration ranges given in accordance with the 

allowed variation 2

. The concentrations of each substance should be specific, but if these concentrations are 

variable the range should be quoted. If the toxicity tests are carried out on a preparation, the concentrations 

of each substance in the formulation used in the toxicity tests should be quoted to enable authorities to assign 

correct relevance to these test values. 

21. All substances, known to be deliberately added, including those present at less than 1% by weight of 

an entire preparation, should be declared. Substances (except those stated in paragraph 1.7 of the OSPAR 

Recommendation 2000/5 on a Harmonised Offshore Chemical Notification Format (HOCNF)), which are 

not deliberately added and are present at less than 1% by weight should not be declared.

22. Where a CAS number is not available for polymers give the CAS number for the monomer on which 

it is based. The latest OSPAR List of Substances / Preparations Used and Discharged Offshore Which are 

Considered to Pose Little or no Risk to the Environment (PLONOR) can be found on the OSPAR website 

(www.ospar.org). 

23. Where generic descriptions are given such as tall oil soaps, polyoxyalkylated glycols, 

phenol/formaldehyde resins, reaction-products, copolymer series (on non-confidential HOCNFs supplied to 

operators) the source materials should be given, together with the best description of the range of major 

substances/preparations present. Where solvents or other additives are refinery or petrochemical products 

consisting mainly or entirely of hydrocarbons, the generic description (e.g. straight-chain alkenes, 3-5 ring 

aromatics) should be given together with the concentrations of any aromatics, and the method used for 

determination should be stated. 

24. Please note that trade names will not be accepted as compositional information.

 

2 Concentration ranges: 

Initial concentration range of the constituent Permitted variation in initial concentration of the constituent 

< 2,5% + 15% 

> 2,5 < 10% + 10% 

> 10 < 25% + 6% 

> 25 < 50% + 5% 

> 50 < 100% + 2,5% 
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OSPAR Commission Summary Record OIC 2003 OIC 03/15/1-E, Annex 6 

§ 1.7 Contents

25. For substances/preparations for which knowledge of the raw materials and manufacturing processes 

involved indicate that the substances will not be present, select the 'NO' box for all categories. Supportive 

evidence for the above should be provided where available in the 'Comments' box. 

26. Annex 2 of the OSPAR Strategy with regard to Hazardous Substances and the latest version of the 

OSPAR List of initially selected substances of possible concern can be downloaded from the OSPAR 

website (www.ospar.org). 

Part 2 Ecotoxicological Information 

27. Ecotoxicological information can be mandatory, conditional or optional. If the offshore chemical is 

on the PLONOR List or all the relevant ecotoxicological information has already been submitted to the 

authority, Part 2 of Appendix 1 to OSPAR Recommendation 2000/5 on a Harmonised Offshore Chemical 

Notification Format (HOCNF) need not be completed. 

28. Ecotoxicological data will only be accepted from tests performed according to international standard 

protocols or guidelines (as e.g. the OSPAR guidelines, ISO test guidelines and OECD test guidelines) and 

prepared by laboratories working in compliance with the OECD Good Laboratory Practice or laboratories 

approved by national authorities. Test laboratories should follow the OSPAR Guidelines for Toxicity Testing 

of Substances and Preparations Used and Discharged Offshore whenever samples are received for testing. 

The testing laboratories should confirm to the supplier, in every case, that the validity criteria for the 

reference test have been met. Literature data of high quality (testing according to acceptable protocols and 

GLP or equivalent accreditation) should be accepted. References should be provided for literature data. 

§ 2.1 Partitioning and bioaccumulation potential 

29. N-octanol water partitioning data are required for all organic substances with the exception of those 

with surface active properties. For preparations, individual information on all deliberately added substances 

is required. This can be estimated by measuring or calculating the partitioning of the substances between 

water and n-octanol (Pow). 

30. Log Pow is used for two purposes. In the pre-screening (OSPAR Recommendation 2000/4) to advise 

on bioaccumulation potential and in the CHARM model to estimate how a substance partitions between oil 

and water with the aim of predicting the environmental concentration (PEC). As a consequence of this dual 

use of log Pow data, whenever a range of log Pow values is quoted in the report, the maximum and 

minimum value should be stated in the HOCNF. The maximum values will be used for estimating 

bioaccumulation potential and the minimum as an indication of the potential of the substance to partition into 

the water phase. 

31. A standard method (shake flask) for the determination of Pow is: OECD Guidelines for Testing of 

Chemicals, 1981-107. The shake flask method is applicable for substances that are water soluble and which 

do not dissociate or associate. The method is not applicable for lipophilic organic substances (of low water 

solubility), preparations, complex substances, organo-metallic compounds and surface active substances. 

Log Pow values in the range –2 to 4 can be measured by this method. 

32. A standard method (HPLC method) for the estimation of the log Pow is: OECD Guidelines for 

Testing of Chemicals, 1989 - 117. This method is applicable for preparations and complex substances. For 

HPLC estimations for complex substances the log Pow range needs to be stated. Ionisable substances should 

be measured in their unionised form under appropriate pH conditions (pH range of natural seawater). The 

HPLC method is not applicable to strong acids and bases, metal complexes, substances reacting with the 

eluent or surface active substances. Log Pow values in the range 0 to 6 can be estimated using the HPLC 

method. 
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OSPAR Commission Summary Record OIC 2003 OIC 03/15/1-E, Annex 6 

33. Reliable methods are now available for calculation of log Pow for many types of organic substances 

and often laboratory testing can be avoided. Examples of reliable methods are CLOGP, LOGKOW and 

AUTOLOGP (cf. European Commission (1996), Technical guidance documents in support of the 

Commission Directive 93/67/EEC on risk assessment for new notified substances and the Commission 

Regulation (EC) No. 1488/94 on risk assessment for existing substances. Part III. Care should be employed 

when using models to assess substances for which the protocols have not been verified. 

34. If the calculated or experimentally determined log Pow ≥3, bioaccumulation will be assumed unless 

experimental bioconcentration factor (BCF) tests indicate the opposite. While high molecular weight 

compounds are less likely to bioaccumulate a precise threshold is not recognised. BCF data are relevant for 

all deliberately added substances whose log Pow >3. The BCF is determined on the basis of the ratio of 

animal tissue concentration to water concentration of the test substance at equilibrium, or on the basis of the 

ratio of the uptake and depuration rate constants. The authority should be consulted beforehand to ensure that 

the test method proposed is suitable. In general, for fully water miscible substances/preparations, either a fish 

or a bivalve mollusc bioaccumulation test would usually be appropriate (e.g. OECD 305 or ASTM E1022), 

whereas a substance/preparation that gives rises to suspended particles may be more suitably tested with a 

filter feeding organism such as a bivalve mollusc. 

35. The presence of surface active substances may increase the bioavailability of other substances in 

preparations. Therefore a bioconcentration test may be required for such preparations. In such a test, 

exposure to the preparation should be followed by analysis of the test animals conducted on a substance by 

substances basis. The relevant bioconcentration test should be agreed in consultation with the authority. 

Where an inappropriate test for a particular preparation/substance has been used, the authority will reserve 

the right to classify the preparation/substance as bioaccumulative. The Mytilus or a fish species would be 

suitable as test organisms, but other test species may also be appropriate. 

§ 2.2 Biodegradability 

36. Data on biodegradability in the marine environment are relevant for all organic substances. For 

preparations or complex mixtures, individual information for all substances deliberately added is requested. 

37. If the substance is found not to be readily biodegradable or if a ready aerobic biodegradation test has 

not been performed, it will be assumed to be persistent in aerobic conditions unless an inherent test is 

performed which indicates the opposite. The relevance of an inherent biodegradation test should be agreed in 

consultation with the authority. 

38. Substances for which no biodegradation data are available shall be tested according to the standard 

test methods for biodegradability: OECD Guidelines for Testing of Chemicals, 1992, 306, or any of the four 

protocols published in the report “Biodegradability of chemicals in sea water”. Results of a ring tests 

undertaken by OSPARCOM, were reported by Elf Akvamiljö, September 1996.” Authorities may accept 

data from freshwater tests according to OECD Guidelines for Testing of Chemicals, 1992, 301 A-F if these 

are already available. The OSPAR ring test is available on the OSPAR website (www.ospar.org). 

39. The highest value for percentage of biodegradation during the 28 days of testing shall be used as the 

biodegradation potential provided that it is not an outlayer. The substance will be considered persistent if the 

biodegradation is <20% in 28 days. 

40. Aerobic inherent biodegradability may be required by authorities. The standard test methods for 

inherent biodegradability are: OECD Guidelines for testing of chemicals, 1981 302 A-C. 

41. Tests on substances known to be toxic to microbes (e.g. biocides) should follow the 

recommendations in Annex II of OECD 1992 301. (UK to review and advise on alternative text) 

42. Biodegradability tests on poorly soluble materials should follow the recommendations set out in 

ECETOC Technical Report No. 20 (1986) Annex III of OECD 1992 301 and ISO Guidance Document ISO 

10634. 
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OSPAR Commission Summary Record OIC 2003 OIC 03/15/1-E, Annex 6 

43. For substances or substances in preparations which qualify for a sediment reworker toxicity test, an 

anaerobic biodegradation test may be conducted in addition to aerobic tests. If such a test is not conducted, 

the substance will be assumed to be non-biodegradable in anaerobic conditions. 

44. Anaerobic biodegradability testing should be carried out following the recommendations set out in 

e.g. the draft OECD guideline: “Aerobic and anaerobic transformation in aquatic sediment systems”, OECD 

308, OECD 2000. Data from anaerobic screening tests conducted with digested sewage sludge (e.g. ISO 

11734) cannot be used for predicting the biodegradation potential in sediments. Anaerobic biodegradability 

data are not relevant for water soluble materials which do not adsorb to surfaces. 

45. Authorities may require additional biodegradation data, e.g. seawater simulation studies, seabed 

survey. 

§ 2.3 Taint 

46. Preparations/substances known or expected to cause taint (the ability of a substance to impart a 

foreign flavour or odour to the flesh of fish and shellfish) will receive a taint warning. A list of compounds 

liable to cause taint is included in the OSPAR List of Substances/Compounds Liable to Cause Taint, which 

is available on the OSPAR website (www.ospar.org). 

§ 2.4 Aquatic toxicity 

47. Toxicity data must be provided for all preparations or their constituent substances, unless they 

appear on the PLONOR List. Marine data should be provided where possible but competent authorities may 

at their discretion accept freshwater toxicity data in place of marine data. 

48. The relevance of toxicity test data other than that specified in this notification format should be 

agreed in consultation with the relevant authority. However, for freshwater data or non-OSPAR marine data, 

application of safety factors as required by the CHARM model may be needed. For certain substances, 

additional marine toxicity data may be required at any time if evidence supports doubt on the relevance of 

existing test data. 

49. For new substances and preparations and, where relevant, for re-notification of existing substances 

or preparations, testing on representative algae, crustacean and fish species is mandatory1

. The full OSPAR 

marine toxicity data set comprises: 

a. Skeletonema costatum; to ISO/DIS protocol 10253 

b. Acartia tonsa; to ISO protocol TC 147/SC5/WG2

c. Scophthalmus maximus (juveniles); to Part B of the OSPAR Protocols on Methods for 

the Testing of Chemicals Used in the Offshore Industry (published by OSPAR in 1995, 

available from the OSPAR web site www.ospar.org) 

A comparative suite of alternative marine or freshwater species are also acceptable if tests are conducted to 

recognised protocols. 

 

1

 If testing another species has already identified a substance for substitution, the fish test is not mandatory 

although it may still be required at the discretion of the competent authority. 
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OSPAR Commission Summary Record OIC 2003 OIC 03/15/1-E, Annex 6 

50. Additionally substances and preparations which: 

a. are "sinkers"; or 

b. have a Koc >1000 (see 2.5); or 

c. have a log Pow>4; or 

d. are in any other way known to adsorb to particles or end up in the sediment (e.g. contains 

surface active substances of the type which enhance adsorption to particles); 

require a sediment reworker test with Corophium spp using Part A of the OSPAR Protocols on Methods for 

the Testing of Chemicals Used in the Offshore Industry. 

51. If available, long-term toxicity test data should be provided. 

52. Where freshwater data is provided, tests must be conducted on representative algae, crustacean and 

fish, and conducted to recognised International standards. Data must be generated by laboratories working to 

Good Laboratory Practice or equivalent internationally recognised standards and a full reference must be 

given for the source of the data. In the case of published data, a copy of the original paper must also be 

provided detailing a full description of the test procedures. 

2.5 Adsorbability 

53. The organic carbon adsorption coefficient (Koc) is only applicable for individual substances. The 

Koc can generally be calculated from the octanol/water partition coefficient (log Pow) and the organic 

carbon content of the sediment and suspended solids. Where this cannot be done, Shake-Flask measurements 

of Koc using marine sediments and seawater may be provided. Suitable methods of calculation and 

measurement are described in Karickhoff, S.W., Brown, D.S.,. and Scott, T.A. (1979), Water Research 

13:241-248. 

54. For surface active substances, measured Koc data are mandatory and the methodology used should 

be stated. SEBA 2000 recognised that at present there are no standard test methods available which would 

provide reliable and robust Koc data for surface active substances. SEBA 2000 therefore agreed to initiate the 

collection of information and literature references to evaluate existing methodology. 

2.6 Mammalian toxicity 

55. Data from mammalian toxicity test for food chain risks should be stated if available. 

Part 3 Confirmation Statement 

56. The confirmation statement is a written declaration renewable every three years to confirm that: 

a. The information in the form still applies precisely to the substance/preparation being 

manufactured or supplied under that specific trade name. Any change in formulation, by the 

addition of any new substance, or the removal of any existing substance, other than by trace 

quantities (<100 ppm or <0,01%), necessitates the immediate action to consider whether new 

data are required. Any change in composition, i.e., in the concentrations of a substance, unless 

within the previously accepted range of variability, similarly necessitates the immediate 

evaluation of the new composition. Any change of name, coding or number requires an 

immediate declaration that the existing format now applies to this renamed preparation; 

b. All tests referred to in Appendix 1 to OSPAR Recommendation 2000/5 on a Harmonised 

Offshore Chemical Notification Format (HOCNF) were carried out in accordance with the 

OECD principles of Good Laboratory Practice (cf. also § 20 above). 
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OSPAR Commission Summary Record OIC 2003 OIC 03/15/1-E, Annex 6 

57. Suppliers may be asked at any time to submit samples of substances/preparations to governmental 

bodies for analysis or testing. Offshore users may also be asked at any time to submit to governmental bodies 

a sample of the preparation currently in use. 

58. Before the renewal date the notifier should consult the national authorities. More relevant or missing 

data on substances/preparations which were previously accepted for use, may be required. 
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OSPAR Commission Summary Record OIC 2003 OIC 03/15/1-E, Annex 6 

Appendix 1 

Glossary and Definitions of Terms 

1. For the purpose of these guidelines and for the purpose of the Harmonised Offshore Chemical 

Notification Format (HOCNF) as at Appendix 1 of OSPAR Recommendation 2000/5 on a Harmonised 

Offshore Chemical Notification Format (HOCNF): 

a. "authority" means the competent national authority of a Contracting Party to the OSPAR 

Convention; 

b. “discharge” means the operational release of offshore chemicals or their degradation and 

transformation products into the maritime area; 

c. "EINECS" means European Inventory of Existing Commercial Chemical Substances; 

d. “ELINCS” means European List of Notified Chemical Substances; 

e. “offshore chemicals” means all chemicals intentionally used in connection with offshore 

exploration and production activities in the maritime area. Offshore chemicals comprise both 

substances and preparations; 

f. "persistent" means a substance biodegrades less than 20% in 28 days; 

g. "PLONOR" means the OSPAR List of Substances/Preparations Used and Discharged Offshore 

Which are Considered to Pose Little or No Risk to the Environment 

h. “Pow” is equivalent to Kow and means the partition coefficient of a substance between octanol and 

water, measured or calculated according to the HOCNF; 

i. “preparation” means a mixture or solution composed of two or more substances; 

j. “SDS” means Safety Data Sheet according to EC Commission Directive 91/155/EC of 5 March 

1991 defining and laying down the detailed arrangements for the system of specific information 

relating to dangerous preparations in implementation of Article 10 of Directive 88/379/EEC or 

any document that may supersede this. 

k. "sinkers" means those chemicals with a density greater than that of sea water and with a low 

water solubility; 

l. “substance” means a chemical element or compound in the natural state or obtained by any 

production process, including any additive necessary to preserve the stability of the product and 

any impurity deriving from the process used, but excluding any solvent which may be separated 

without affecting the stability of the substance or changing its composition; 

m. "trace" means a substance is represented with less than 0,01 % (<100 ppm) in a preparation; 

n. “use” means application of any offshore chemical in connection with offshore exploration and 

production activities in the maritime area that might result in discharge. 

2. Further definitions and information can be found in: 

• OSPAR Decision 2000/2 on a Harmonised Mandatory Control System for the Use and 

Reduction of the Discharge of Offshore Chemicals; 

• OSPAR Recommendation 2000/4 on a Harmonised Pre-screening Scheme for Offshore 

Chemicals; 

• OSPAR Recommendation 2000/5 on a Harmonised Offshore Chemical Notification Format 

(HOCNF); 

which are available for downloading from the OSPAR web site (www.ospar.org). 
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OSPAR Commission Summary Record OIC 2003 OIC 03/15/1-E, Annex 6 

Appendix 2*

Functions of Chemicals referred to in paragraph 7 of the OSPAR Guidelines for completing 

the HOCNF 

Acidity Control Chemical 

Antifoam (Hydrocarbons) 

Antifoam (Water Injection) 

Asphaltene Dissolver 

Asphaltene Inhibitor 

Biocide 

Brine (Completion) 

Carrier Solvent 

Cement or Cement Additive 

Coagulant 

Coolant or Coolant Additive 

Corrosion Inhibitor 

Crosslinking Chemical 

Cuttings Wash Fluid 

Defoamer (Drilling) 

Demulsifier 

Deoiler 

Detergent / Cleaning Fluid 

Dispersant 

Drilling Lubricant 

Dye 

Emulsifier 

Filter Cake Removal Chemical 

Filter Media or Filter Media Additive 

Filtrate Reducer 

Flocculant 

Fluid Loss Control Chemical 

Gas Hydrate Inhibitor 

Gelling Chemical 

Hydraulic Fluid 

Hydrogen Sulphide Scavenger 

Lost Circulation Material 

OPF Additive 

OPF Base Oil 

OPF Base Synthetic 

OPF Oil based Drilling fluid 

OPF Synthetic-based Drilling Fluid 

Oxygen Scavenger 

Pipe Dope 

Pipe Release Chemical 

Pipeline Hydrotest Chemical 

Pipeline Pigging Chemical 

Proppant 

Scale Dissolver 

Scale Inhibitor 

Shale Inhibitor / Encapsulator 

Thinner 

Tracer chemical 

Viscosifier 

Water Based Drilling Fluid Additive 

Water Based Drilling Fluid 

Water Clarifier 

Wax Inhibitor 

Wax Dissolver 

Weighting Chemical 

Well Stimulation Chemical 

Well Bore Clean-up Chemical 

Other 

 

*

 This appendix has now been agreed in a written procedure between OIC Heads of Delegation.