safety awareness topic of the month€¦ · it is important that preventive maintenance systems...

ModuResources (Australia) Pty Ltd

[email protected]

Suite 4, 123 Melville Pde,

Como, WA 6164 T: +61 8 9417 6933

17/67 Depot Street, Banyo,

QLD 4014 Australia T: +61 7 3357 5004

1 Bukit Batok Street 22, #03-01,

Singapore 659592

T: +65 6265 3353

1127 Eldridge Parkway,

Houston, Texas, USA 77077 T: +1 281 899 0076

Safety Awareness Topic of the Month

Electrical Safety

Recently a number of safety observations have revealed some simple items that present

serious hazards, with very simple corrective actions.

Details (Figure 1):

Whilst carrying out a check on electrical items, it was noted that several rescue hooks were

missing. This hook is used to assist in the rescue of personnel by dragging them away from

the source of electrocution.

Details (Figure 2):

Appropriate approved cable joining should be used at all times, or the cable replaced.

AS/NZ3000:2007

It is important that preventive maintenance systems promote regular inspections of safety

equipment points, particularly relating to rescue equipment. It is also recommended that these

checks are added to regular equipment checks.

“Safety risks are not yours to take; you’re not the only one who will suffer from

your mistakes!”

If you have colleagues who wish to be included in this monthly safety bulletin, please send their contact details to us and we will gladly include them.

Date of issue: 28th February 2018

Figure 1: Shows the location where the

rescue hook should be. Figure 2: Cable terminations / entries

with sheathing cut short, and splices with

only electrical tape, including cable

repairs using electrical tape.

mailto:[email protected]


[email protected]


Como, WA 6164 T: +61 8 9417 6933


QLD 4014 Australia T: +61 7 3357 5004


Singapore 659592

T: +65 6265 3353

1127 Eldridge Parkway,



Fire Safety

Figure 1 H2S gas detector was mounted at height.

Figure 2 Thermal overload protection element of this circuit breaker was bypassed with big copper wires.

From the recent inspections carried out, there were several critical findings noted concerning

fire safety equipment and fire risk increased by bad practices/neglect at electrical equipment.

During the survey, it was noted that several of the H2S gas detectors were mounted at

position which was a considerable distance away from deck level and would not be able to

work as per design (Figure 1). Some were also noted to be with error / warning messages

displayed. It was recommended that the H2S gas detectors are installed close to deck for

proper detection as H2S is heavier than air. (Refer to IMO 2009 MODU Code section 9.12.1)

Also, ensure that the rig fire and gas detection is part of the rig PMS. All detection systems

along with sensors/detectors shall be identified, tasks specified, and the time intervals

between tests stated.

There was a circuit breaker inside the main switchboard where its thermal overload

protection element was bypassed with big copper wires. This is a potential fire hazard and

the overload relay should be replaced immediately. (Refer to IMO 2009 MODU Code section

5.6.13) It was also recommended to ensure that circuit breakers and thermal overloads are

tested through current injection test periodically. (Refer to IEEE 242 sections 16.5 to 16.15;

NFPA 70B chapter 11; AS/NZS 3019:2007 Section 2.8/5.6/5.8)

Date of issue: 28th March 2018



[email protected]

Suite 4, 123 Melville

Pde, Como, WA 6152

T: +61 8 9417 6938


QLD 4014 Australia

T: +61 7 3357 5004


Singapore 659592 T: +65 6265 3353

15835 Park Ten Place, Suite

105, Houston, TX, USA 77084

T: +1 832 416 0098


Line of Fire

Figure 1 Automated drilling rig

Figure 2 Line of Sight

1. If you can touch a control/lever/button and make movement somewhere else that has

potential to cause harm, how is this managed?

2. How is your equipment operated?

Touch Screen, Lever, Joystick or Button Operated Equipment?

How do you manage the risk of inadvertent operation of the equipment?

What is the method of shutting down equipment after a joystick/lever failure?

3. Risk Assess your operation for:

a) Line of Fire Does the operator of the equipment have a full view of equipment movement?

b) Exclusion Zones What are the exclusion zones for your equipment?

c) Isolations When do you isolate this equipment? How do you isolate this equipment?

d) ESDs Are ESD’s fitted and tested regularly and do you record any equipment movement?

4. How do you manage activities that require personnel to be in the area of automated equipment?

5. What is your management of change process associated with safety critical equipment?

Be aware of the constantly changing work environment around you!

Identify the ‘Line of Fire’ hazards in your Risk Assessments!

Eliminate the need to work in the ‘Line of Fire’ where practicable!

Document and implement the controls of your risk assessment!

Monitor ‘Line of Fire’ hazards through adequate supervision!

Date of issue: 30th April 2018


ModuResources (Australia) Pty Ltd [email protected]

Suite 4, 123 Melville Pde, Como, WA 6152 T: +61 8 9417 6938

17/67 Depot Street, Banyo, QLD 4014 Australia T: +61 7 3357 5004


Singapore 659592 T: +65 6265 3353

15835 Park Ten Place, Suite 105, Houston, TX, USA 77084

T: +1 832 416 0098


Working at Heights

The issue was discussed with the drilling contractor’s responsible supervisor and the suggestion was made that retractable fall arrest lanyard reels (Sala-type blocks) should be utilised. Overhead beams and other suitable overhead attachment points were available at several locations from which retractable fall arrest lanyard reels could be hung. Utilisation of these provided the workers the ability to be permanently attached to a fall arrest system whilst working at height, without the use of double lanyards and the necessity to look for suitable hang-off points when moving around the work area. Self-retracting lanyards and safety harnesses may be used with a static line or fixed anchorages.

Date of issue: 31st May 2018

A recent inspection carried out highlighted several critical findings concerning working on heights and the use of overhead hang off points.

Whilst observing the progress of the work on a well control system’s components (namely the Choke and Kill manifolds) it was noted that the crew working at heights, removing the valves and pipe work were utilising fall arrest harnesses with double lanyards. However, at times unsuitable hang-off points were utilised which were lower than waist height. This was mainly due to the lack of suitable overhead hang-off points available above the area of work.


Date of issue: 30th June 2018


[email protected]

1 Bukit Batok Street 22,

#03-01, Singapore 659592 T: +65 6265 3353


Como, Perth, WA 6152 T: +61 8 9417 6938

17/67 Depot Street,

Banyo, QLD 4014 Australia T: +61 7 3357 5004

Mill House, Balgownie Road

Bridge of Don, Aberdeen, AB23 8JN, UK T: +44 (0)7753 470 288

15835, Park Ten Place, Suite 105,



Transport and Travel

Travel should always be an area of concern for all enterprises especially when tight time frames

are involved.

For off-shore workers this can involve a

minimum of driving a vehicle from home

to an airport and a helicopter flight or

boat transfer out to the workplace. In

many cases an additional flight may be

involved between airports necessitating

the workers to rise early and travel by

vehicle during the hours of darkness.

With the advent of more and more remote workplace locations onshore, these workers also

often experience similar travel modes with the addition of a further vehicle transit to complete

their journey.

The majority of work in our industry is deemed fly-in / fly-out and as with all workers their

travel needs must be met in a manner which promotes their maximum safety and wellbeing.

It is important when planning travel arrangements that each individual workers’ needs are

clearly understood, and appropriate arrangements are made to minimise their fatigue.

Considerations to allow for include such items as: their travel time to the airport; known peak

traffic periods to allow for, or preferably avoid; the minimum time required by the airline for

baggage deposit, ticket collection and any clearances before departure; also the journey rest

periods stipulated by company rules; and any sustenance requirements.

The transport industry already has very clear and concise regulatory rules which must be

followed with regards to truck driver rest periods, travel times, log books etc.

Over recent years there have been a number of fatalities, often involving single vehicles, of

workers driving whilst fatigued, both on their way to the job and traveling home.

DON’T let your workers add their names to those whom fatigue has claimed.

PLAN their travel arrangements well and keep them as safe as possible.



#03-01, Singapore 659592 T: +65 6265 3353


Como, Perth, WA 6152 T: +61 8 9200 3430

17/67 Depot Street,

Banyo, QLD 4014 Australia T: +61 7 3357 5004


Bridge of Don, Aberdeen, AB23 8JN, UK T: +44 (0)7753 470 288

15835 Park Ten Place, Suite 105,



The Prevention of Dropped Objects

This is commonly known as DROPS and the golden rules here are; keep everything as simple

as possible, conduct regular inspections and treat every site individually (this is particularly

important when improvements are being made, or have been made on sister rigs as retention

methods can differ).

There are multiple DROPS prevention methods available to designers and end users of

equipment. However, following a few basics simplifies prevention requirements:

For permanent structures that require no disassembly, welding is the preferred option.

Regular periodic inspection of the welds preferably undertaken without damage to the

coating material is best practice. Any repairs necessary should be done at the earliest

possible opportunity by competent welders using the OEM guidelines.

For bolted structures the simplest and most effective secondary retention is the use of

wedge type washers. Even under the most severe conditions these will not allow the bolts

to vibrate and loosen when correctly installed as per the OEM recommendations. The

advantage with these is they may be reused multiple times as can the bolts and nuts.

Pinned items should where possible have a cross bolt or at least a split pin sized to fit.

Some OEM equipment e.g. Top Drive utilises safety wire - always reinstall it correctly.

As mentioned in a previous safety bulletin, almost all pressure hose failures occur close to

the ferrule. Suitably installed rated whip socks prevent both flail injuries and DROPS. It is

important here to follow the OEM installation instructions, normally a minor amount of free

play in the legs (10 – 15mm) and the alignment of anchor points with the hose. If your

company preference is for the use of whip checks these also need to be kept as short as

possible and aligned with the anchorages.

Temporary items require additional thought prior to installation. Where possible use one of

the preceding methods. Clamps are a commonly used item where no other method is

possible but care is required to ensure coatings remain undamaged. This is of particular

importance in corrosive atmospheres e.g. offshore.

When undertaking maintenance where DROPS may occur, each individual worker should

take the appropriate arrangements to minimise the risk. Usually this is accomplished by

using tethered tools and storage devices e.g. tool belt or satchel, no-go zones, checklists of

items in use, checking the area is clear of loose items, and verification of the safety

arrangements and any permit requirements.

Over recent years there have been a large number of near hits, some serious injuries and some

fatalities as a result of dropped objects.

The wedge type washers, Nord-lock X series are shown here,

one of the types available to reduce the likelihood of a

DROPS incident.

http://www.nord-lock.com/nord-lock/wedge-locking/customer-specials/


#03-01, Singapore 659592

T: +65 6265 3353


Como, Perth, WA 6152

T: +61 8 9417 6938


QLD 4014 Australia

T: +61 7 3357 5004


Bridge of Don, Aberdeen, AB23 8JN, UK

T: +44 (0)7753 470 288

13501 Katy Freeway, #1422

Houston, Texas, USA 77079

T: +1 281 899 0076


Common Mode Voltage due to VFDs

Date of Issue: 30th August 2018

Variable frequency drives (VFDs) have

largely replaced SCRs drives on new rigs.

Issues relating to harmonic voltage

distortion should be addressed during the

design phase and resolved. However,

VFDs, if not installed in full compliance

with EMC recommendations which

requires special ‘VFD cables’ to the

motors, dedicated EMC glands and

equipotential grounding, can produce a

phenomenon called “common mode

voltage” (CMV). The result is the VFD

IGBT inverter switching frequency

superimposed on the phase to ground

voltages.

Susceptible equipment connected to the

same ground can be subject to spurious

disruption (e.g. control and measurement

systems, plcs, safety& alarms systems,

HMIs, etc.)

Recently, a rig was unable to operate for

an extended period of time due to the

drawworks and top drive VFD common

mode voltage affecting the control

systems on cranes and other equipment.

Tens of millions of dollars in costs were

incurred before the matter was resolved.

Below is the pulse train from a rig fire

and gas detection system. LHS are

normal pulses. The RHS pulse show the

interference due to a 315kW VFD

brought onboard and not installed

correctly. The result was numerous,

spurious fire and gas alarms and

resultant evacuations.

[email protected]

Common mode current travels from the

VFD to ground through the motor

bearings. Micro-arcs at the VFD

switching frequency produces flutes

which damages/destroys the bearings.

On VFD fed EExd explosion-proof

motors, the additional danger of

flameproof gap degradation exists in

extreme cases, resulting in the risk of

ignition of gases or vapours external to

the motor carcass.

If you are experiencing unexplained

disruptions and/or VFD fed motor

bearing problems, the cause may be

associated to common mode voltage.

Pulse traces from fire and gas detection system.

LHS is normal. RHS was distortion due to CMV.

SENTINEL POWER QUALITY

OIL AND GAS



[email protected]


#03-01, Singapore 659592

T: +65 6265 3353



T: +61 8 9417 6938

17/67 Depot Street,

Banyo, QLD 4014 Australia

T: +61 7 3357 5004



T: +44 (0)7753 470 288

1127 Eldridge Parkway, Suite 300-

340, Houston, Texas, USA 77077

T: +1 832 416 0098


Choke and Kill Systems – Target Blocks/Fittings

Date of Issue: September 2018

At the time of a recent selection survey

for a new-build rig, the ModuResources’ Surveyors noted that

some of the 90-degree target blocks for the rig’s choke and kill system had

been incorrectly installed, with respect to flow direction.

In this instance, the approved P&IDs were reviewed, flow direction traced

and confirmed, and the Client notified of the error and assistance requested to address prior to mobilization of the

rig.

This finding is a subtle reminder to thoroughly inspect and verify installations per approved drawings,

and a great lesson learnt with respect to due diligence (3rd party overview)

before acceptance of rigs prior to mobilisation.

In this case, a relatively simple fix in the shipyard, that would have been

more difficult to complete offshore.



High Pressure

High pressure in engineering and scientific circles is usually considered to be any pressure

exceeding a thousand atmospheres (1013.25 bars or 14,700 psi.) However, the dangers of

pressure are apparent at much lower pressures than this.

With the advent of more automated equipment on both offshore and onshore rigs yet more

pressurised systems have been brought into play. There has for example been a massive

increase in the use of electrically or pneumatically controlled hydraulic systems.

High pressure systems regardless of the medium should be maintained by competent persons

in accordance with the manufacturer’s recommendations. Records should be kept of all service,

repairs and maintenance.

It is important when planning maintenance that each individual worker clearly understands the

appropriate arrangements required to minimise their exposure to risk. Considerations to allow

for include such items as: inspection methodology, pressure testing, isolation of the system,

depressurisation of any accumulators and other storage devices, lock out / tag out of the

operating controls, no go zones, verification of the safety arrangements by a competent person

and any permit requirements.

Over recent years there have been a number of serious injuries and in some cases fatalities as

a result of unexpected pressure discharges. The retention arrangements of pressurised hoses

are often not clearly understood. With almost all pressure hose failures occurring close to the

ferrule suitably installed rated whip socks prevent flail injuries.

Many of the newer rigs now enclose the hydraulic hoses in burst protection sleeves which help

to eliminate fluid penetration injuries. Penetration of the skin can occur at pressures as low as

100psi (700kN/m2) and up to 4” (100mm) away from the fluid source.

A PERTH worker's arm following surgery to

place an artificial vein in his forearm after a

jet of grease, about one teaspoon, was

injected into his little finger. If not treated

promptly and effectively, these injuries can

lead to amputation or death as the

mechanical and chemical factors lead to

compartment syndrome and subsequently

systemic intoxication. The amputation risk

is lowered if wide surgical debridement

occurs within 6 hours of injury.

PLAN and implement the prevention and maintenance arrangements of all pressure systems

to keep your personnel as safe as possible.

Date of issue: October 2018


#03-01, Singapore 659592

T: +65 6265 3353



T: +61 8 9417 6938


QLD 4014 Australia

T: +61 7 3357 5004



T: +44 (0)7753 470 288

13501 Katy Freeway, #1422

Houston, Texas, USA 77079

T: +1 281 899 0076

safety awareness topic of the month€¦ · it is important that preventive maintenance systems...

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