Portable Level Gauging Devices

Limitations of presently available Cargo Tank Portable Level gauging devices:


During a recent correspondence with the makers of Portable tank gauging instruments, it has been highlighted that so far no UTI's are available on the market for use on corrosive liquids, such as Sulphuric acid. Majority of the UTI's are IIB classified, while for gauging acids, IIC classified products are required.

Enraf Honeywell GTEX UTImeter have come up with a specific sensot, called Ultra sensor, which can withstand specific chemicals, such as acids. This special sensor would be able to stand sulphuric acid without any comparison with the standard sensor considering however that this part as the rest of the device shall be cleaned with an appropriate solution after every measuring campaign to neutralize the corrosive effect of this acid. However, this sensor is still IIB certified.

Below from the makers of Enraf:

Quote----

Lastly, I would like to highlight that:
     - our STANDARD SENSORS DO NOT WITHSTAND and MUST NOT BE USED TO GAUGE SULPHURIC ACID. Only specific sensors equipped with a beige sensor head equipped with a metallic cap can withstand sulphuric acid (difference between standard Ultra sensors and specific sensors for specific chemicals).
     - Referring to IBC Code, Section 11.5 Acids, our units shall not be used to gauge sulphuric acid. I recommend anybody to assess the suitability of our devices before using it to gauge acids and more specifically sulphuric acid. See attached letter.
     - The units must be cleaned after every measurement campaign with an appropriate solution to neutralize the acids

----- Unquote


On a seperate issue, for Bitumen / Asphalt carriers, vessel's carrying cargoes at higher temperatures, like 150 DegC +, it is important to understand that all UTI's presently available in the market are only capable of measuring upto 90 DegC.

In short, there are no gas-tight device available off the shelf, as yet for using for measuring ullage / temperatures at high temperature. Asphalt temperatures could be as high as 180 Deg C.

In such case, it will be better to have onboard a Closed Sounding tape for ullaging only.

Further, for temperature measurement, that is where the real problem lies. For this, the best possibilities are (unless the UTI maker can provide an alternative solution – awaiting the details) to take a sample of the cargo, using the closed sampler and use a Marine Thermometer of range of 200 DegC to measure temperature, if need arises, with Risk Assessment done prior to usage. However, mostly in such cases, the tank fixed thermometers are always preferred and predominantly used, and thus it is imperative that the system is kept calibrated and serviced as soon as a problem is discovered.

Hope you’ve some spare temperature sensors for the system on board. If not, it may be prudent to request for a few standby sensors.


All I can think of is a modified system made of a normal brass marine thermometer of range upto 200DegC connecting to a normal sounding tape (minus the bob / weight) and inserted in the tank, if required, on each occasion through the vapor locks.

Further, understand, these thermometers will require to be yearly calibrated, preferably ashore or by a calibrated standard temperature device onboard to cover up SIRE / cargo surveyor requirements.

Good luck guys.

For Himanshu and others who may be interested

Dear all,
I finally found that someone does follow me - well this gentleman did and he asked me some questions, to which I've tried to answer. For others to think over, I'm reproducing them here.

1) Can U give a note(guidance) on making loading plan for an aframax/vlcc,Where loading rate is fast (10,000 m3/hr.)


My Ans:

Loading or discharging plans for smaller / bigger vessels is the same. Most important is for you to know the limitations of the vessel. Check your stability booklet for such. If you’ve U-shaped ballast tanks etc.

Every vessel’s pumping / loading arrangements are made basis the same consideration or ratio; rate of loading / discharge vis-à-vis the tank capacities. Accordingly, if you go on a small tanker of 30000T DWT, the max. pumping rate for homogeneous cargo will be about 3000 m3/hr, while if you go to a 100000 T DWT tanker, the pumping rates will be 10000 M3/hr.

This is always designed keeping in mind the filling rate and/or so the vapour displacement rate (P/V valve throughput etc.).

For developing any cargo plan, the most practical approach will be, in my opinion, as this is what I used to do –

1)    Work out your initial (ballast, no-cargo) stowage and stability and the final (all cargo) stowage and stability conditions.
2)    Your job is half done, once you’ve the above two conditions in hand.
3)    Next, assuming your question is for VLCC / Suezmax etc., means homogeneous cargo, start first foot loading in all tanks, that is work out a stage, where all your tanks or the first set of cargo tanks are filled about 0.5 – 1 m innage. During this time, you can start the loading at slow rate as per your ship’s design and shore agreement. Also you’ll start deballasting by gravity. Work out this condition on loadicator and compute the result, always keeping stern trim and maintaining vessel stability. Drafts should always agree with MARPOL criteria of max trim and minimum propeller immersion draft.
4)    At the next stage, you can start filling up tanks and reducing ballast slowly, always approaching your final condition, which you’ve already worked out earlier in stage 1. Continue deballasting keeping in mind the draft / favourable trim and stability.
5)    Always keep the amidships tanks slackest, available for the end. This would ensure that your ship does not develop sag, and towards the end, when you’re completing cargo loading, you’ll not have to keep resolving unusual trim.
6)    Multiple conditions will have to be worked for intermediate stages of loading, and this has nothing to do with time. As you work out, each stage will tell you, how much cargo has been taken in, and you’ll find that you have the time for each stage in hand, basis the available rates.
7)    At each stage, you’ll have to be careful about de-ballasting rates, since that has to be kept up with loading condition / stage too.
8)    In case, if you find that de-ballasting may be a problem, the best solution is to commence de-ballasting as soon as possible and prolong the initial slow loading rate stage and gradually increasing the rate of loading to max. Also towards the end, you can ask for decrease of rate in view of topping off.
9)    Keep an eye on the IG rates etc. to ensure it is coping up.
10) Actual topping off can be done towards the end. From my experience of stage loading, I’ve found its relatively easy to top-off tanks without having to reduce rate right until the end. What you have to do is plan your loading in such a way that each tank has a different level towards completion. This means on a bar graph if you see, you’ll have the cargo tanks filled with max. cargo on the extreme end (foremost and last) tanks, and gradually reducing to the centre. As you start topping off the end tanks, you can continue loading in the next set of tanks, changing over as you continue topping off, and as you reach closer to the last set of tanks, ask terminal to reduce rate. However, try this only if you are sure you are able to do this.

I’ve attached the cargo plan documents that I’d made during my own service as Chief Officer and now incorporated as company docs in my present company. You’ll have to amend the wordings, as these are more suitable in the present form for the chemical tankers.

Further questions:

Pls clarify on following pts-

1)Ford most & aft most tank will have least ullage,in case of heavy wx,during pitching oil/vapours may come out from ford tanks.

2) At discharge port,I can discharge those set of tanks which are nearly same,till all the tanks have come to nearly same level.

My Answers:

1)Ford most & aft most tank will have least ullage,in case of heavy wx,during pitching oil/vapours may come out from ford tanks.

The simplest explanation for this in layman terms is the principle of moments. Consider the fact that when a vessel is making way, its centre is the pivot point. Right? Now this Pivot point gets displaced or basically you can say that the loads along the scale passing through the pivot point keeps changing, causing the vessel to roll, pitch etc. Now the closer you are to this imaginery centre of the vessel, during her movement, you’ll feel less force of movement. However, the furthermost you are from this, the higher will be the resultant motion, with smallest exertion of force (think of Leverage). This would surely explain you, why?

However, it is important for you to understand also, that this is more importantly observed on vessels, where the Cargo tank PV valve orifice is on deck plating (remember normally it should not be constructed this way; it must be in the tank dome above the level of deck plate). With a trim in heavy pitching , cargo from forward will enter the PV pipes with orifice on deck platings and cause splashing on to deck. This would also cause rapid movement of vapours, being forced out of the P/V Valves.

Due to the same leverage, it is probable, in case of poorly maintained manholes on deck, that cargo or vapours may seep through it on deck.

2) At discharge port, I can discharge those set of tanks which are nearly same, till all the tanks have come to nearly same level.

What do you think, will happen (typical of vessels with pumproom ships and COPs in pumproom), when you commence discharge from tanks with different ullage level of cargo? You always commence discharge slowly, and increase it slowly too. Assume you started discharge from two tanks with ullages 3.6m and 1.4m. You will find that most of the cargo is being discharged from the second tank, while the 1^st tank may actually not change or may show an increase only. This is because cargo is getting transferred internally. Your expectations go for a toss.

It is always prudent to discharge the more filled cargo tanks until you are able to achieve a level lower than 88% in all tanks. This gives a safety margin too, in order to act, should there be internal inadvertent transfer of cargo.

Next question:

I noted that' There are numerous blogs, nautical institute site, various flag of registry sites, which provide you a lot of information.' Can you please name some of them for which I will be very grateful to you.

My Answer:

For Nautical Institute try www.nautinst.org

Various Classification societies have their own news feed, check them on their websites BV/LR/DNV/ABS etc.

For various Flag news, check

http://www.mantamaritime.com/

Marshall Islands: http://www.register-iri.com/

Liberia: http://www.liscr.com/liscr/

Panama: http://www.segumar.com/

Other sites:

http://www.safety4sea.com/

http://shipsbusiness.com/

http://gisis.imo.org/Public/

http://www.shipinspection.eu/

http://gcaptain.com/

http://pinoymaritime.com/blog/

http://mymaritimeblog.wordpress.com/

Blogs check as follows:

http://barratry.blogs.lloydslist.com/

http://ajitvadakayil.blogspot.com/

http://internationalshippingnews.blogspot.com/

http://theworldofshipping.wordpress.com/

http://kennebeccaptain.blogspot.com

http://www.lawandsea.net/maritime

http://www.themaritimesite.com/the-best-nautical-and-maritime-blogs/

Finally, anything you wish to get the knowledge on, just do a google search on it. I personally believe people blog for the reason of sharing the knowledge and experience. 

Remain objective in your search for a query, do not be judgmental, and you'll find the answers you are looking for.

ISM 10.3 - Critical and Standby Equipment

ISM 10 MAINTENANCE OF THE SHIP AND EQUIPMENT

10.1 The Company should establish procedures to ensure that the ship is maintained in conformity with the provisions of the relevant rules and regulations and with any additional requirements which may be established by the Company.

10.2 In meeting these requirements the Company should ensure that:

.1 inspections are held at appropriate intervals;

.2 any non-conformity is reported, with its possible cause, if known;

.3 appropriate corrective action is taken; and

.4 records of these activities are maintained.

10.3 The Company should identify equipment and technical systems the sudden operational failure of which may result in hazardous situations. The safety management system should provide for specific measures aimed at promoting the reliability of such equipment or systems. These measures should include the regular testing of stand-by arrangements and equipment or technical systems that are not in continuous use.

10.4 The inspections mentioned in 10.2 as well as the measures referred to in 10.3 should be integrated into the ship's operational maintenance routine.

I've noted that a majority of deficiencies and / or non-conformities that are raised on vessels are dealing with non-performance of Standby Equipment. While majority of the companies have realized that the inspections by superintendents is not adequate, they've also realized that not all Stand-by Equipment are covered in the Planned Maintenance Systems of the vessels.

What are the Stand-by Equipment?

Dictionaries would define these as a secondary system identical to the main system, to be used if the main system breaks down. In principle, these would and should include all such Equipment or Machinery that would qualify to be called in action during Emergencies, thus LSA, FFA & Emergency Machinery. 

However, since ISM does not really give a clear definition of the term, it is left to wide interpretation by all individuals. In a worst case scenario, only the Emergency Equipment are treated as such.

Let's first differentiate between Critical Equipment and Stand-by equipment.

Critical Equipment and systems are those where loss of functional capability or failure to respond when activated manually or automatically, may create a hazardous situation and / or cause an accident.

Identifying Critical Equipment:

Critical equipment is identified by the Shore Management by making a risk assessment taking following aspects into consideration:

•    Which equipment;

•    Impact on crew, vessel or environment if not working;

•    Back-up equipment / system;

•    Likelihood of failure.

A proper methodology should be developed, including identification of hazards for critical equipment failure, existing control methods, and evaluate the residual risk. If the residual risk is low, the Equipment will not be called Critical. However, if the residual risk is high, and further control methods can still not lower the risk, the Equipment will have to be called Critical and thus processes will have to be identified to nullify the risk, including substitutes, minimum spares etc.

Dealing with each equipment, identified as Critical will need to have a procedure to act, in the form of a checklist, if any of these equipment fail, including any trainings, drills etc to mitigate the consequences.

Stand-by Equipment:

In very short, something that we do not use everyday on board the ships. Let’s look what all would be considered Stand-by Equipment. In my opinion, it automatically includes all Emergency Equipment, by virtue of use during Emergencies.

Therefore as a minimum the following would be included:

1)            Life Saving Appliances & Equipment;

2)            Fire Fighting Appliances & Equipment;

3)            Emergency Generator, Emergency Air Compressor and other Compressors like BA bottles charging compressors;

4)            All Vents, Flaps, Fire doors, Fire divisions;

5)            Oil Spill Equipment, including any portable or fixed pumps;

6)            Emergency Bilge Pumping arrangements;

and such other. You being on board would know better, which equipment you’ll require in Emergency. I feel, tools required to operate / repair / maintain these equipment too would come under this purview. This implies there should be an existing stock, clear description and identification of such tools, be it hydrant opening spanners or a wrench / hammer.

What else?

Let’s see, on a typical tanker (guys, I’m a tanker-man, so please work about other type of vessels accordingly), we walk from Forward to aft.

7)        Anchors, bitter end arrangements, including tools.

8)        Forepeak Store W/t door, including sealing and closing arrangements.

9)        All forward stores sealing and closing arrangements, including doors.

10)      Bow Thruster room, booby hatches, other booby hatches forward.

11)      Suez Light and lifting arrangement on Foc’s’le.

12)      Bitts, Chain Bow Stoppers, Emergency Towing Equipment forward and aft, Bollards, Fairleads, Rollers, Winches, Windlass, ropes / wires mooring as well as supporting ones like heaving lines and stoppers.

13)      Eductors

14)      Anchor Chain Wash line and valves

15)      Any hoses (cargo, hydraulic, pneumatic, FRAMO etc.) kept on board.

16)      Cleaning material (minor, but imagine, working on a chemical tanker, having used previously on caustic soda remains, the equipment is now being used trying to control an acidic cargo outflow). But then, it should have been disposed of after cleaning in the first place. That is why you are supposed to inspect, because this was not done.

17)      Any and all valves on all pipelines, store ventilators, vents, flaps, closing appliances, mechanical ventilation devices etc.

18)      All manhole covers for cargo / ballast tanks and void spaces, vents etc.

19)      The void spaces and pipelines passing through them, including any valves located in them.

20)      Ladders, MOT or ship’s gangways.

21)      P/V Valves, Mast-Risers, P/V Breakers, IG Pipelines, cargo equipment, emergency hydraulic pumps, hydraulic and manual valve actuators, controls, boxes, lines etc.

22)      Deck pipelines, shafts etc. continuity cables etc.

23)      Dresser couplings or expansion joints.

24)      All Spectacle Flanges, blank flanges, spare reducers for cargo / bunkering etc., nuts and bolts, gaskets etc.

25)      Nitrogen bottles, room, connections and lines, if applicable.

26)      VECS

27)      Drip trays drains, cocks, valves and scuppers.

28)      Deck scuppers.

29)      All Cranes, wires, associated winches, drums etc.

30)      All bunker and cargo davits, fixed and portable

31)      Bunker tank vents, valves and lines

32)      Cargo pipelines, including tank cleaning / COW lines, valves etc.

33)      Pressure / Compound gauges, thermometers, IG gauges and connections

34)      All cargo tank fixed and portable gauging devices, including vapour locks, grounding devices etc.

35)      Pilot ladders and Pilot boarding arrangements

36)      Drain lines, cocks etc.

37)      IG line, deck seals, scrubber, IGG and valves, including all locking arrangements.

38)      Deck security equipment, including all padlocks, seals etc.

39)      All W/T doors on all decks.

40)      Deck lighting, emergency as well as normal

41)      Portable cargo lights, pneumatic or otherwise.

42)      All Bridge and Radio Equipment, navigational or communication, including mast lights, flag halyards, signal lamps – fixed and portable, Comm Equipment Antenna etc.

43)      ODMCS

44)      Overboard valves, Overboard discharge Annex I & Annex II arrangements

45)      In Engine Room, all valves, stand-by pumps and all lines,

46)      Oily Water Separator and 15 ppm equipment

47)      Emergency Sludge transfer arrangements.

48)      Sewage discharge connections

49)      Bunker manifold valves

50)      All Emergency Stops on the vessel

51)      220V & 440V alarm panels

52)      All other alarm panels

53)      Sample lockers, chemical lockers etc.

54)      CO2 room lines, cocks, and alarms etc.

55)      Pumproom alarms, lines, valves etc.

56)      Pumproom Exxon connection for Sea chest

57)      All blanks and spool pieces on deck or in pumproom.

58)      All loose lifting gear including chain blocks, slings, shackles etc.

59)      All fixed / portable gas measuring devices and instruments

60)      All measuring / calibration equipment

The list is not exhaustive, and can be continued. In short, I’ll say that everything, that seems to be the least important part / equipment of the ship and the risk of getting neglected is high, and which also will continue to remain on board, despite not being used, as a part of the ship, all that you may think of, as “may be required, so let’s keep it properly’ will be included. Some may not agree with me in my this description of Standy-by equipment, but trust me, there’s always more then what meets the eye to ISM.

Some of you may feel that, it is foolish to include just about everything as stand-by equipment. To you, I’ll ask one question. You may be the best in management, take care of each part of the vessel, the safeties etc. in terms of maintenance or inspections, so then the auditor or any inspector for that matter will have nothing to observe. How many of you have come across an inspector who always picks up easily, what you thought is not worthy of attention?

Let’s just say there is no end to it, and besides as a prudent ship-manager or sailor, why do you think the owners employed you in the first place? To take care of everything on board the vessel, I guess. Do you think, parts being missed in “taking care” is appreciated?

Think and apply. Think again and apply, and if you still feel that now I’m going overboard, well, my friend, my advice to you is simple. I believe learning can be two ways, one by other’s experience, one by own experience. Whatever you may prefer! You'll see the reason someday@!

Good luck in maintaining your vessel!

Drager Toxic Gas Detector Extension Hoses Correction Factor

Drager Chemical Gas Detection Tubes - Correction Factors for Extension Hoses.


Recently, one of my friends posted a question to our alumni Group mail, in regards to correction factor required to be used for some of the Drager tubes when used with Extension Hoses. This is not really applicable to all tubes, but only to some of them.


The query was as follows:

I have recently came across documentation in a Drager instruction manual which stated that when tubes are used in conjunction with 10 or 15 metre length extension hoses, a correction factor requires to be applied for certain tubes. The reading obtained on the tube requires to be multiplied by this correction factor. As can be seen, the gases this applies to are those which are commonly encountered on board ships.

The problem now is that Drager does not manufacture hoses in lengths greater than 15 metres, but can and do supply these if they are specifically ordered. If a hose of greater length is used, there are no clearly defined correction factors available. You will note from the attachment to this message that the factors for a 15 metre length are greater than those for a 10 metre length. It therefore follows that as the length increases, the factor that requires to be applied should logically increase. I am not entirely sure for the reason for this correction factor, but it could have something to do with the atmospheric pressure differential between the pump and the tube. 

Information on the use of extension hoses with other Draeger Tubes is available upon request. 

Tel. 4511882808

Measurement by means of 1Om and 15m extension hoses

Single-stroke measurement

Draw the sampling air through the tube with 1 pump stroke. When the stroke is finished -the white indicator mark on the pump becomes visible - allow for a waiting period of 2 minutes before removing the tube from the sampling point. Evaluation is effected in accordance with the instructions for use of the tube in question. Correction of the measuring result is not required for the single-stroke  measurement. 

Several-stroke measurement

Draw the sampling air through the tube with the specified number of strokes. Always perform the next

stroke once the white indicator mark becomes visible. No waiting period is required after the final stroke. If several-stroke measurement is performed by means of 10 m or 15 m extension hoses, the tube

reading of some of the Drager Tubes must be multiplied by a correction factor (See attached pages on this blog).

Now the first question is why? Why is a correction required?

The reason is most trivial and dates back to high school physics.

With a 3 m extension hose, the error is immaterial and is not worthy of consideration. I would not be very wrong in saying the same for even 5m hose. In fact, if your measurements are based on single stroke measurement, no correction is required to be applied with 10m or 15m tube lengths. It is only required to be used, when you have multiple stroke measurements with a tube.

The reason can be found in the way the chemical reactions take place in the tube. A number of chemical reactions are used in such tubes and these include :

1. rapid reactions which are independent of the flow rate through the tube;
2. rapid reactions with secondary reactions which may depend on the flow rate through the tube; 
3. consecutive reactions in which the vapor reacts with one reagent to produce products that are detected by reaction with a second reagent; 
4. reactions where a large excess of reagent is necessary.

For tubes involving reactions (3) and (4), flow rate is often critical because the reaction rate with the reagent can be slow. In addition some tubes involve the use of a pre-cleansing layer of a reagent which is intended to remove possible interfering substances.

And the flow rate is definitely affected by the length of hose. Why? Bernoulli’s Theorem…guess simple physics. Weight of the tube, causes elongation, causes the tube dia to reduce, causes change in flow rate.

What correction to apply?

Now what correction factor to apply with a tube of greater length (>15m) will need to be confirmed from Drager themselves. However, I’ve not come across anywhere, where greater then 15m length tubes are used. So drager has not provided further guidance too.

The volume which is conveyed with each pump stroke is not changed when the extension hose is used, however, the flow characteristic which is typical of the Drager gas detector pump may be subject to changes. This in turn results in a change of the opening time of the gas detector pump. For some Drager Tubes in conjunction with 10 or 15-meter extension hoses, such change is liable to cause errors in the readings. The reading must therefore be corrected. Given a hose length of 3 m, however, the change in the opening time is so insignificant that the influence on the measuring result can be neglected in any case. 

However, my friend did come up with a possible calculation - 

Drager tubes are calibrated at an atmospheric pressure of 1013 hPa (i.e. 1013 mbar), to correct for the influence of pressure, the value read from the tube scale must be multiplied by following correction:

Correction Factor = 1013 hPa (14.692 psi) / actual atmospheric pressure in hPa

The atmospheric pressure can be calculated by following formula:
P = 101325 (1 - 2.25577 10-5 h)5.25588
Where P= air pressure (Pa) and h = altitude above/below sea level (m)

I do not agree with this correction methodology, since then it would affect all types of tubes, not only some of them. It has more to do with the flow rate. 

Should any one know more, please do let me know.

Bridge Navigational Watch Alarm System (BNWAS) July 2012 due date!

Bridge Navigational Watch Alarm System (BNWAS) requirement
New buildings and existing ships need to be equipped with (BNWAS) in order to monitor bridge activity and detect bridge officers disability which could lead to marine accidents. Although due dates for existing ships are first periodical survey (annual intermediate, renewal) after 1 July 2012 the earliest, it is advisable to arrange retrofitting in forth coming Dry Docking/SS/ITSS. In this post you will find what BNWAS is and applicable dates depending on vessels type and size.

Application dates
SOLAS Ch.V Reg.19 as amended by res. MSC.282(86), adopted on 2009-06-05, has introduced a carriage requirement for BNWAS as follows:

1. Cargo ships > 150 GT and All Passenger ships constructed on or after 1 July 2011;
2. All Passenger ships constructed before 1 July 2011, first survey after 1 July 2012;
3. Cargo ships > 3000 GT constructed before 1 July 2011, first survey after 1 July 2012;
4. Cargo ships > 500 GT but < 3000 GT constructed before 1 July 2011, first survey after 1 July 2013; and
5. Cargo ships >150 GT but < 500 GT constructed before 1 July 2011, first survey after 1 July 2014.

Description of requirement
This Bridge Navigation Watch Alarm System (BNWAS) in simple terms is a timer alarm system that forces watch officers to reset this system in periodic time intervals to insure that they are fully alerted (not sleeping, playing solitaire with bridge computer,etc).

The requirement has the following main technical characteristics:

• After the system has been activated no alarm for a period of 3 to 12 minutes. 
• After this period the system initiates a visual alarm on the bridge
• If not reset with a period of 15 seconds an audible alarm on the bridge is activated. 
• If not reset with a period of 15 seconds from last audible bridge alarm, a second stage audible alarm is activated in a remote location (ships office, master office).
• If not reset a third stage alarm is activated in a remotely location were other officers can take corrective action within 90 seconds from the initiation of second stage alarm. 
• In vessels other than passenger vessels the second and the third stage alarms may sound in all of the above location at the same time. 
• In larger vessels time delay between second and third alarm can be set up to a maximum of 3 minutes. 

RESET Function

• It should not be possible to initiate the reset function or cancel the audible alarm from a device not physically located in the bridge area providing proper lock out. 
• The reset function should be a single operation function. 
• The single operation reset action must be in such a way that will ensure mental alertness of the OOWS. 
• The dormant periods should not be able to be prolonged by continued activations or any reset devices. 

Better to start working on it now, then later.