What are the major causes of accidents
Physical hazards Ignorance Over familiarity Laziness Preoccupation Horseplay
How do we tackle the accident problem
Know the hazard- know the precaution
Maintain safety discipline
Develop habit of noticing potential danger
What are the 3 main cause of electric shock
Equipment failure
Human failure
Combination of both
What happens to the body when exposed to these Electric currents: 1mA
20mA
10mA
30m
1mA = involuntary reaction
20mA physical damage
10mA - prevents from releasing hold
30mA- can kill
What voltage on board is considered to be safe
24VDC
What is the correct electric shock procedure
- LVA
- isolate person from supply
- if you can’t use wood or something else to Get them away
- check for response
- keep shouting for help
- check airway
- check breathing
- Keep shouting for help
- cpr if first aid trained 30 compressions 2 rescue breaths
Before tagging out a piece of equipment what 3 steps must be carried out
- Obtain permission from senior rate ME to carry out isolations
- All isolation points are to be identified
- equipment user must be informed
Describe the procedure for removing fuses
- Place finger in the centre of the fuse holder firmly
- With the free hand unscrew the fuse holder w fuse key
- grab the the fuse holder, turn head and remove & remove the fuse holder
- remove the fuse from holder put the empty fuse holder back to maintain a dead front
- repeat for second & third fuse way
Dangerous components and their hazard on board HM ships
Tantalum capacitors - explodes & releases sulphuric acid -wear face protection
Selenium rectifiers - toxic dust released when they burn out - wear rubber gloves & face protection
Penetone tpc lotoxane - 53 flash point 12 month shelf life don’t spray on named flames and hot surfaces - rubber gloves fan upper deck & face covering
What PPE should be worn when working in the galley?
DMS BOOTS
CHEFS HAT
OVERALLS OR 4S SLEEVES ROLLED UP
How are all galley supplies isolated in the event of a fire?
All supplies have isolation switches outside galley painted red
What is the biggest fire hazard within the galley
Deep fat fryer due to high oil temp of 180-190 degrees
What are the precautions to be taken when working on LIVE electrical equipment (8marks)
- Don’t Take risks
- rubber gloves
- use insulated tools
- don’t use short circuits
- wear insulated footwear
- don’t work alone
- work with one hand if you can
- check test equipment is up to date
- stand on rubber mats
- be awAre of voltages
Precautions to take when working on DEAD equipment
- Isolate and carry out LOTO procedure
- prove equipment is dead using GPTME
- discharge capacitors using GPTME set to volts
- fit shorting straps when needed to prevent capacitors from recharging
What is the procedure to follow when removing a LOTO
- obtain permission
- sign LOTO safety certificate for removAL
- collect the correct fuses, Part B&C label
- make sure circuit isolation switches are open
- Remove part A and empty fuse holder, using a GPTME set voltage measure across the empty fuse way, if it’s 0 put the fuse back in fuse holder and the fuse holder back in fuse way then repeat for fuseway 2&3
- Return LOTO labels ABC to senior rate
- Sign safety certificate for LOTO removal &closure
- close LOTO index sheet entry
- Destroy label put certificate in section 6 of log book
What specific PPE should you wear when working on Tantalum capacitor
Face protection
3 types of hand change over switches
Normal/alternative
Normal/emergency
Normal/alternative/emergency
What should happen to labels after reinstating a tag-out
Removed and destroyed
What is the resistance of the human body, when dry
1k omega / 1000 omega
Why avert your eyes when removing fuses
In case of sparks
When carrying out a tag - out where should part B go
On the tag out board
Why are shorting straps fitted to capacitors during maintenance
To prevent them from recharging
When is it considered safe to work in live electrical equipment
When supervised by a senior rate
Three categories for radioactive valves
Class 1 theta sign
Class 2 “class 2”
Hazard “caution”
