48280 Title 33-Navigation and Navigable Waters CHAPTER I-COAST GUARD, PART 151---OIL POLLUTION PART 157-RULES AND REGULATIONS Tank Vessels Carrying Oil in Domestic Purpose. The purpose of these amend. ments to the pollution regulations is to add regulations that govern the design and operation of seagoing U.S. tank ships and barges of 150 gross tons and over that carry oil in the United States domestic trade. These regulations will effect in the immediate future a significant reduction of operational pollution from tank cleaning and deballasting operations from seagoing U.S. tank vessels in domestic trade. Additionally, these regulations will be extended to encompass the remainder of the U.S. seagoing vessels and foreign vessels trading into U.S. waters. Pollution caused by vessel casualties will be diminished as a consequence of the regulations. In the January 26, 1973 issue of the FEDERAL REGISTER (38 FR 2467), the Coast Guard published an advance notice of proposed rulemaking inviting comments from the public on proposed requirements for certain tank vessels to have segregated ballast that would be achieved in part by the fitting throughout the cargo length of double bottoms. In the July 5, 1973 issue of the FEDERAL REGISTER (38 FR 17848), a notice was published informing the public that the Coast Guard intended to withhold action on the Advance Notice of Proposed Rulemaking until the International Conference on Marine Pollution, 1973 was concluded and the results of that meeting evaluated. After the Conference in October 1973, there followed a period of study and debate within the Coast Guard and with other federal agencies concerned with marine pollution prevention. Several policy questions had to be resolved (1) Should the United States accept the international standards specified in the International Convention for the Prevention of Pollution from Ships, 1973, or should unilateral action be taken to impose higher construction standards on U.S. vessels and foreign vessels entering our waters? (2) If the United States were to accept the Convention standards which would apply to foreign ships and U.S. ships in foreign trade, what standards should be adopted for U.S. vessels in domestic trade? (3) Should economic, social, legal, foreign policy, and safety considerations be reflected in the formulation of the regulations? After considering the issues raised by these questions, the Coast Guard decided that the Convention although not perfect. did establish a reasonable and en RULES AND REGULATIONS vironmentally effective set of standards on which regulations for tank vessel construction could be based. The Coast Guard also decided that pollution regulations for all U.S. seagoing tank ships should be uniform, irrespective of the trade in which they are engaged. Based on these two decisions, proposed regulations conforming to the provisions of the Convention were published in the June 28, 1974 issue of the FEDERAL REGISTER 39 FR 24150). In developing the proposed regulations. the Coast Guard also complied with the mandate contained in Title II of the Ports and Waterways Safety Act of 1972 146 U.S.C. 391a) to consider: the need for such regulations, the extent to which such regulations will contribute to safety and or protection of the marine environment; and the practicability of compliance with the regulations, including cost and technical feasibility. In response to public and Congressional comment, the Coast Guard has reviewed the basis for the proposal and reaffirms its decision to base the regulations on the 1973 International Convention. Pollution of the oceans must be viewed as an international problem. Ocean winds and currents do not observe national boundaries. Many of the ocean areas of greatest productivity of sea life lie in international waters beyond the jurisdiction of any nation. World shipping and trade in petroleum are international in scope, with only a small portion of the US. supply of petroleum being transported in ships of American registry. Therefore, ship source pollution problems are best attacked in an international context with unilateral action reserved for those circumstances when international solutions are impossible or inappropriate. Because of its potential effectiveness in reducing operational pollution, the best course of action is the implementation of the Convention coupled with vigorous efforts by the Coast Guard to improve crew training, manning standards, and operating standards for the reduction of both operational and accidental outflows. A number of commenters asked why the Coast Guard did not distinguish between foreign and domestic trade and provide higher standards for U.S. vessels engaged in domestic trade. Some commenters interpreted Title II of the Ports and Waterways Safety Act of 1972 (46 U.S.C. 391a), as amended by Section 401 of the Trans-Alaska Pipeline Authorization Act (Public Law 93.153, 87 Stat. 576, as establishing that distinction In the Coast Guard's opinion, the law does not permit a distinction between domestic and foreign vessels to be inferred from any treaty, convention, or international agreement. In addition, there is no safety or environmental basis for setting higher standards for U.S. domestic trade vessels since the characteristics of the operational situation external to the vessel determine the threat to the environment and to the safety of the vessel, not whether the vessel is engaged in foreign or domestic trade. Accordingly, there is no inandate to issue. for US. tank vessels engaged in carrying oil in domestic trade, rules which set a higher standard than those rules that will app to other U.S. vessels and to foreign vessels while in United States jurisdictio Existing regulations governing tanker construction and operation. issued under R.S. 4417a, as amended 46 USC 391 and promulgated in 46 CFR Subchapters D and O, make no distinction between tank vessels engaged in domestic trade and those engaged in foreign trade. Requirements for seagoing tank vessels have been based on the vessel size, the duration of the voyage. the exposure to hazards (ie.. bad weather, rough sea conditions, vessel traffic, and the characteristics of the cargo carried. If distinctions in tanker construction requirements concerned with safety and pollution prevention were to be based on "foreign" and "domestic trade routes, the result would be different standards for vessels engaged in essentially identical voyage routes. For example, a vessel on a foreign" voyage from a Caribbean port, another on a "domestic voyage from the Gulf coast, both sailing along the east coast of the United States. are subject to identical risks. The Coast Guard has concluded that safety requirements should be concerned with the risks involved and not on trade route distinctions. Another reason for not distinguishing between tankers in foreign and domestic trade is the need to allow owners the flexibility to use vessels in either trade as business opportunities change. Several commenters doubted the validity of this reason. Therefore. the Coast Guard examined the voyage records of 272 U.S. seagoing tank vessels; only 66 vessels had engaged exclusively in domestic trade during the sample time period Those 66 were generally vessels of less than 15.000 gross tons, and at least 15 were carrying bulk cargoes other than petroleum, such as sulphur, wine. and similar dry and liquid cargoes. Since the amendments are based on the Convention. several commenters suggested that the Convention wording be used. While adequate for the purposes of international agreement for implementa tion by states parties, the language of the Convention is not in all cases considered by the Coast Guard as being specifie enough for legal sufficiency. There were several comments concerting the dates in the definition of "new vessel" each of which proposed a delay in the applicability of the requirements The Coast Guard found no support for further delay and accordingly did not adopt the suggested changes. Several commenters suggested that the Coast Guard should establish cutoff dates after which existing vessels not fully in compliance with the proposed requirements for new vessels would be removed from service in U.S. waters. Existing vesels are required to be upgraded by the use of slop tanks. separators, oil discharge monitoring and control systems. and the alteration of piping. These are design and equipment requirements that will improve the ability of the vessel to FEDERAL REGISTER, VOL 40, NO 199--TUESDAY, OCTOBER 14, 1975 avoid routine operational discharges It is not practicable to retroactively apply. the segregated ballast requirements of these regulations to existing vessels The Coast Guard is participating in a study of the cost and feasibility of some type of retrofitted segregated ballast requirement This study is being conducted by a working group of the National Committee for the Prevention of Marine Pollution The proposed revision to the oil record book requirement in 151.35(c)(1) (v) has been changed to state that it is applicable only to the side valves, that is, the valves on the cargo transfer manifold where the oil is transferred to or from the shore during loading or discharge. The remainder of the valves in the oil and ballast system are covered by the other entries in the oil record book. Several commenters suggested that the definition of clean ballast in proposed 157.03 (e is not clear and differs from the Convention meaning. The proposed definition agrees with current U.S. regulations (see 40 CFR Part 110 and has not been changed. Discussions between the Coast Guard and the Environmental Protection Agency are being held on the question of whether confirmation by monitor records that a discharge did not exceed 15 parts per million oil in water provides a legal defense. Changes in the regulations may be proposed after these discussions. One commenter noted that the proposed definition of deadweight in 157.03 g) was at variance with the Convention and this definition has been changed to conform with the Convention. Several commenters suggested that petrochemicals should be excluded from the proposed definition of, "oil" Petrochemicals have not been classified with respect to pollution potential. When 46 CFR Subchapter 0 is revised to incorporate the provisions of Annex II of the Convention, the classification problem will be addressed in more detail. As suggested, petrochemicals are now excluded from the definition of oil. The definition has been reworded for clarification. One commenter suggested that the definition of segregated ballast in proposed 157.03 (r) should include the Convention alternative of ballast cargoes other than oil or noxious substances. This suggestion has not been adopted since no substances have been identified or suggested for regular use as an alternative to water ballast. One commenter questioned whether proposed 157.05 (a) represented a step toward adoption of the metric system. The formulas in these regulations require conversion from customary units to SI units before entering values into the formulas. This use of the metric system will increase in the coming years. One commenter suggested that the Commandant of the Coast Guard should reserve the option of accepting an operating requirement in lieu of a construction requirement under proposed 157.07. The adoption of that suggestion would confict with a Convention provision expressly intended to preclude such a practice. The Coast Guard agrees RULES AND REGULATIONS with the Convention philosophy and will not adopt the suggestion. Commenters noted that some requirements of proposed Subpart B are inappropriate for most seagoing tank barges. Generally, unmanned seagoing tank barges do not take ballast into cargo tanks or clean cargo tanks while at sea. Accordingly, 157.08 has been rewritten and 157.28 has been added to reflect this operating practice. Also, 157.08 has been changed to exempt barges constructed to inland standards from the requirements in §§ 157.19 and 157.21. Many commenters were critical of the fact that the segregated ballast requirement in proposed 157.09 did not include vessels smaller than 70,000 tonnage DWT. The United States negotiating position at the Conference was in favor of extending the segregated ballast requirements to all new vessels of 20.000 tonnage DWT or more, but this position was not accepted by the majority at the Conference. Discussion at the Conference for and against extending segregated ballast requirements to cover vessels from 20.000 tonnage DWT to 70,000 tonnage DWT centered on the effectiveness of such requirements in reducing operational pollution. Segregated ballast would not be effective in preventing operational pollution from tank vessels smaller than 70.000 tonnage DWT because most of these vessels carry petroleum products rather than crude oil. These vessels must frequently wash tanks for cargo purity reasons. Since clean cargo tanks are then available for ballasting, segregated ballast is unnecessary. Proposed $157.09(b) (redesignated $157.09(a)) concerning segregated ballast tank capacity has been revised in response to criticism that the proposal created an unreasonable burden on the shipbuilder and shipowner to show the adequacy of segregated ballast capacity for ballast voyages. The master must have a vessel with adequate segregated ballast capacity for safe operation. The amount of ballast needed for safe operation is a matter that in the past has been usually left to the judgment of the vessel's master. Considerable effort on the part of naval architects, shipowners, and government agencies has gone into trying to determine a reasonable ballast level for most circumstances. The draft and trim requirements in the Convention, contained in proposed 157.09 (c) (redesignated 157.09(b)), are based on the current collective judgment of world experts. The validity of these levels will have to be verified by satisfactory operating experience in the future. The responsibility for determining how much ballast is needed for safe operations remains with the vessel's master. He may take additional ballast in cargo tanks during severe weather if in his judgment it is necessary (see § 157.35). Comments indicated that the proposal was not clear as to whether the draft and trim requirements are design criteria or operating restrictions. Section 157.09 (b) has been changed to require the designed-in segregated ballast capacity to be sufficient for the ship to meet the draft and trim requirements in any ballast condition including the condition "lightweight with only segregated ballast" Bection 157 09 (d) (redesignated 157.09 (c)) has been changed to allow additional ballast to be carried in more than one cargo tank under abnormally severe weather conditions, 85 described in $157.35 Many commenters were critical of the fact that the proposed regulations did not require double bottoms. In addition. the proposal did not contain standards concerned with the specific placement of segregated ballast within the vessel. The commenters suggested that if segregated ballast was needed to control operational pollution, it should be distributed to serve as protective space to mitigate the outflow in cases of collisions, rammings, and groundings. Though the Convention does not specify how segregated ballast spaces should be distributed, the suggestion that the spaces can have a secondary use by proper arrangement to give some protection in the case of accidents has merit. A new paragraph (d) has been added to 157.09 to state the requirement that was unstated but implicit in proposal: distribution of the segregated ballast must be acceptable to the Coast Guard. On page 48289 in this issue of the FEDERAL REGISTER the Coast Guard publishes a notice of proposed rulemaking amending these rules. These proposed changes relate specifically to the limited issue of how the required segregated ballast must be distributed. Proposed 157.11 has been reworded for clarification. Paragraph (c) has been changed to state that a manifold includes a cargo or ballast manifold that can be used to transfer dirty ballast water or an oily mixture to a reception facility. One comment with respect to proposed 157.13 suggested that the requirement was impractical because in many cases a cantilevered structure extending beyond the deck edge would be necessary to visually observe the discharge. This same commenter suggested that it would be sufficient to observe the effluent in the sea. The Coast Guard rejects this concept on the basis that it is not satisfactory or sufficient to observe the wake. The overboard discharges must be so loIcated to be observed from the deck. In response to several comments, proposed 157.15 has been rewritten. References to bames, weirs, and similar separation aids within the slop tank have been eliminated. The requirement for separate inlet and outlet connections has been retained since this is a basic prerequisite for decanting water from the slop tank. Slop tank design that provides effective and efficient oil/water separation is a developing art so it is not possible to provide specific design requirements at this time. One commenter pointed out that Regulation 15(2) (a) in the Convention provides that on existing vessels any cargo tank may be designated a slop tank if suitable piping is installed. Nothing in the proposal is in conflict with Regula FEDERAL REGISTER, VOL. 40, NO. 199-TUESDAY, OCTOBER 14, 1975 18282 tion 15(2a concerning this use of cargo tanks. The Coast Guard anticipates that existing vessels will be modified to use existing cargo tanks as slop tanks: however, proposed 157.15 has been changed to make it clear that slop tanks may carry cargo as is customary in the Load-On-Top (LOT) methods. Several commenters suggested that "adequate capacity" for the oily residue tank required in proposed 157.17(b) should be more definitively stated. The Coast Guard feels that the owner and shipbuilder are in the best position to determine the capacity needed for oily residue in view of the variables involved. One commenter suggested that the dates in proposed $157.19 concerning cargo tank arrangement and size should be made to correspond with dates defining a new vessel in § 157.03. This is not possible in view of the fact that the dates in this section are established in 33 US.C. 1004a, which is based on IMCO recommendations. In response to several comments, the Coast Guard added an interpretation of paragraph 3.3 of Annex C of the 1971 amendments to the 1954 Convention to the pollution regulations in 33 CFR 151.50 (39 FR 30125). This interpretative rule allows a US. tank barge of 150 meters or less to be constructed with essentially the same bulkhead spacing as a tankship of comparable cargo capacity. One commenter questioned whether sluice gates used in cargo transfer systems are considered "valves" under proposed 157.19 (c). While sluice gates are usually larger and not as tight as gate, globe, or butterfly valves used in cargo systems, the Coast Guard considers them to be "valves" under § 157.19 (c) In response to several comments, proposed 157.19 (d) has been rewritten to require that if a line of piping that runs through a cargo tank in a position less than t. from the vessel's side or less than v. from the vessel's bottom, as defined in Appendix A, has a branch, that branch must have a valve within each cargo tank into which the branch opens. The valve may be at the bulkhead where the branch line enters the tanks, at the end of the branch adjacent to the opening, or anywhere in the branch within the tank. Proposed 157.21(a) (3) (redesignated $157.21 (c)) has been rewritten to state the criteria that must be satisfied in determining acceptable stability after damage. Proposed $157.21(a) (4) has been omitted from the final regulations. The proposal was included to account for cross-flooding: however, cross-flooding was not included in the Convention regulations. One commenter suggested that proposed 157.21(b) (redesignated § 157.24 (b) be rewritten on his assumption that it would be impossible for a designer or builder to submit stability data at the same time the contract plans and specifications are submitted. The Coast Guard considers plan review a continuous process. It is normal practice for a designer to prepare preliminary estimates of a vessel's stability as part of the contract plans and specifications. From the time RULES AND REGULATIONS the Coast Guard review process begins and until the time the vessel is certificated, the calculations can be revised and refined by the submitter. Several commenters felt that the cargo and ballast system information required by proposed § 157.23 is redundant, citing requirements for oil transfer procedures presently contained in 33 CFR 155.750. While there may be some overlap, § 155.750 specifically concerns oil transfer operations at a terminal, but § 157.23 requires information necessary to carry out retention-on-board operations while underway. It may be desirable for some vessels to combine the information required by these rules into one manual. The proposed requirement in $157.23 that the instruction manual be submitted for Coast Guard approval has been omitted. The owner must furnish the vessel a manual containing his vessel's cargo and ballast information, and furnishing the vessel with a copy of the "Clean Seas Guide for Oil Tankers" would not meet this requirement. The information required must be available on board the vessel and for Coast Guard examination during boardings. Several commenters took exception to the prohibition against carrying ballast water in fuel tanks on new vessels contained in proposed § 157.33. The Coast Guard believes that this objection is based upon a misunderstanding of the background of Regulation 14(2) of Annex I of the Convention. It was the intent of the Convention to prohibit ballasting of fuel tanks on new vessels. The abnormal circumstances in Regulation 14(2) refer to a small number of vessels that stay at sea for long periods, such as fishing, whale, factory, or other vessels deployed to remote areas such as the Arctic or Antarctic. Since the proposal did not concern those vessels, the prohibition was not changed. A question on ballasting of fuel tanks concerned the use of a dual purpose ballast/fuel tank (ie., a tank used for fuel when the vessel is on a trade route requiring long voyages and used for ballast when the vessel is on a short voyage route). If a vessel has a dual purpose tank, a requirement will be noted during the Coast Guard plan review process that the piping to the particular dual purpose tank must contain spool pieces that can be inserted into either the fuel piping or the ballast piping depending on how the tank is being used. One comment requested clarification of the phrase "is proceeding enroute" in proposed 157.37(a) (2). The words in this phrase are used in their dictionary meaning which is "moving on or along the way." In other words, the vessel must be moving through the water. It cannot be anchored or drifting. This will not prohibit a vessel from going to sea solely for the purpose of cleaning tanks before entering a repair yard so long as the criteria in § 157.37 are met. One commenter noted that proposed § 157.37(a) (5) (redesignated § 157.37(a) (6)) was incomplete since it did not specify how to operate in case of failure of the automatic oil discharge and monitoring and control system. This paragraph has been rewritten to include requirements in case of failure that allows manual operation of the system. Another commenter suggested that proposed 157.37(b) should have a broader application than only vessels that carry asphalt. This suggestion is not adopted. The only reason an exception exists for asphalt vessels is because of the inability to clean and consolidate the cargo residues while at sea Several commenters noted the impracticability of compliance with proposed § 157.43 in the case of a vessel fitted with double bottoms having no access from the deck. This section has been rewritten to allow the discharge without first visually examining the top of the contents of the tank if the ballast content is tested with an oil water interface detector or a similar device. Proposed 157.45 has been changed to acknowledge that the need for either cargo or ballast transfer may arise while the vessel is at sea necessitating the opening of valves and closing devices. The phrases "closing devices" and "transfer system are used to include those vessels using sluice gates in tank bulkheads. Valves and closing devices are required to be closed at sea, except when in use. in order that the vessel meets the stability requirement. Proposed 157.49 has been changed to reflect its applicability to persons operating cargo and ballast systems of a tank vessel. Several commenters noted an omission in Appendix A for the installation of emergency high suction transfer systems. This was an oversight and this optional installation has now been added to Appendix A. One commenter noted that proposed footnote 2 of paragraph 4(b) in Appendix B appeared to be more stringent than the Convention requirements since it specifies the use of the actual density of the cargo in order to perform the calculations. This was included to ensure that the designers used a representative cargo density in the calculations to rectify the omission of a Convention specification. Proposed paragraph 4(d) of Appendix B has been rewritten to reflect the latest Convention recommendation on free surface effect calculations. In consideration of the foregoing, the proposed regulations that appear in the June 28, 1974 issue of the FEDERAL REGISTER (39 FR 24150) are hereby adopted subject to the changes discussed in the preceding paragraphs. It was Congressional intent that the regulations be effective not later than June 30, 1974 and any further delay would be contrary to public interest. Accordingly, it is found necessary to make the regulations effective on October 14, 1975. A Final Environmental Impact Statement, "Regulations for Tank Vessels Engaged in the Carriage of Oil in Domestic Trade". has been prepared on the regulations in this document, and was made available to the President's Council on Environmental Quality and the public on August 15, 1975. The statement contains additional and more detailed informa FEDERAL REGISTER, VOL. 40, NO. 199-TUESDAY, OCTOBER 14, 1975 tion. Copies are available upon request to the Executive Secretary G-CMC/82), US Coast Guard, Washington, DC 20590. The inflationary impact of the requirements in this document was evaluated in accordance with the criteria contained in the Department's Interim Guidance for the Preparation of Inflation Impact Statements. Under the evaluation, these requirements are found not to be a major proposal and a Negative Declaration has been prepared. Copies are available upon request to the Executive Secretary G-CMC 82, US Coast Guard, Washngton, DC 20590. I certify that the Interim Rules and Regulations for the Protection of the Marine Environment Relating to Tank Vessels Carrying Oil in Domestic Trade is not a major proposal in accordance with Executive Order 11821, dated November 27, 1974. and Departmental implementing instructions. In consideration of the foregoing. chapter 1 of title 33, Code of Federal Regulations, is amended as follows: 1. Section 151.35 (c) and (d) (2) is revised to read as follows: § 131.35 Oil record book. (c) If an operations listed in this paragraph occurs, the Oil Record Book must be completed in accordance with the requirements contained in paragraph (e) of this section. (1) The following operation on A tanker must be recorded on a tank-totank basis: (1) Loading of oil cargo (i) Internal transfer of oil cargo during a voyage. (ii) Opening or closing before and after loading and unloading operations of valves or similar devices that interconnect cargo tanks. (iv) Opening or closing of means of communication between cargo piping and seawater ballast piping. (v) Opening or closing of valves at hose connection points at ends of cargo transfer manifolds before, during, and after loading and unloading operations. (vi) Unloading of oil cargo. (vi) Ballasting of cargo tanks. (viii) Cleaning of cargo tanks. (ix) Discharge of ballast except from segregated ballast tanks. (x) Discharge of water from slop tanks. (xi) Disposal of residues. (xi) Discharge overboard in port or at sea of bilge water accumulated in machinery spaces. (2) The following operations on a ship other than a tanker must be recorded on a tank-to-tank basis: (1) Ballasting, or cleaning during voyage. of bunker fuel tanks. (ii) Disposal of oily residues from bunker fuel tanks or other sources. (d) ... (2) The escape of oil or an oily mixture resulting from (1) damage to the ship: (ii) unavoidable leakage: or (ii) any accident or other exceptional Circumstance. 18283 (c) "Breadth" or "B" means the maximum molded breadth of a vessel in meters. (d) "Center tank" means any tank inboard of a longitudinal bulkhead. (e) "Clean ballast" means the ballast in a cargo tank which. if discharged from a vessel that is stationary into clean, calm water on a clear day, would not (1) produce visible traces of oil on the surface of the water or on adjoining shore lines; or (2) cause a sludge or emulsion to be deposited beneath the surface of the water or upon adjoining shore lines. (f) "Combination carrier" means a vessel designed to carry oil or solid cargoes in bulk (g) "Deadweight" or "DWT" means the difference in metric tons between the lightweight displacement and the total displacement of a vessel measured in water of specific gravity 1.025 at the load waterline corresponding to the assigned summer freeboard. (h) "Lightweight" means the displacement of a vessel in metric tons without cargo, oil fuel, lubricating oil, ballast water, fresh water, and feedwater in tanks, consumable stores. and any persons and their effects. (1) "New Vessel" means a vessel that(1) is constructed under a contract awarded after December 31, 1974; (2) in the absence of a building contract. has the keel laid or is at a similar stage of construction after June 30, 1975; (3) is delivered after December 31, 1977; or (4) has undergone a major conversion for which- (1) the contract is awarded after December 31, 1974; (i) in the absence of a contract, conversion is begun after June 30, 1975; or (ii) conversion is completed after December 31, 1977. (j) "Existing vessel" means any vessel that is not a new vessel. (k) "Major conversion" means a conversion of an existing vessel that (1) substantially alters the dimensions or carrying capacity of the vessel; (2) changes the type of the vessel; or (3) substantially prolongs the vessel's service life. (1) "From the nearest land" means from the baseline from which the territorial sea of the United States is established in accordance with international law. (m) "Instantaneous rate of discharge of of content" means the rate of discharge of oil in liters per hour at any instant, divided by the speed of the vessel in knots at the same instant. (n) "Oil" means oil of any kind or in any form, except petrochemicals, and includes but is not limited to petroleum. fuel oil, sludge, oil refuse, and oil mixed with wastes other than dredged spoil. (o "Oil fuel" means any oil used as fuel for machinery in the vessel in which it is carried. (p) "Oily mixture" means a mixture with any oil content. (q) "Permeability of a space" means the ratio of the volume within a space 69-088 - 7623 FEDERAL REGISTER, VOL. 40, NO. 199-TUESDAY, OCTOBER 14, 1975 |