Nancy Henry HSENI Inspector Lead Inspector for noise and vibration
Nancy Henry
HSENI Inspector
Lead Inspector for noise and vibration
content
� What is the problem
� What are the health effects
� Sources of vibration
� Legal requirements
� Sources of information
� Solutions
� Questions
Courtesy of OPERC
What’s the problem!
� What is hand-arm vibration?
� Hand-arm vibration is vibration transmitted into your hands and arms e.g. when you use hand-held powered work equipment.
� Too much exposure to hand-arm vibration can cause hand-arm vibration syndrome
(HAVS) and carpal tunnel syndrome.
• About 5 million exposed to HAV at work
• About 1 million exposed above ELV
• Greatest numbers in construction industry and
related trades but highest levels in Foundries,
stone masons and heavy fabrication.
Serious, disabling and costly …
… but preventable
Health effects
� Neurological component
� numbness, tingling, reduced
sense of touch & temperature
� main cause of disability in
advanced cases
Health effects
� Vascular component
� “vibration white finger”
� episodes of finger
blanching
� typically cold-induced
attacks
Health effects
Musculoskeletal component
Carpal tunnel syndrome
is a nerve disorder which
may involve pain,
tingling, numbness and
weakness in parts of the
hand.
What causes the problem
Vibrating hand held tools
Mixing plaster Nail gun
Chainsaw
Angle grinder
Hammer action tools
Stationary work piece e.g. grinding,
sanding
Stationery work piece e.g. riveting
hand guided machinery
� Plate compacter� rammer
Hedge cutters
Strimmers
IDENTIFY
• Do your employees regularly operate hammer action tools for more than about 15 minutes per day; or
• Some rotary and other action tools for more than about one hour per day
• You are also at risk if you hold work pieces, which vibrate while being processed e.g. powered machinery such as pedestal grinders.
ASSESS
� Risk assessment – exposure of employee
Legal limits
� Daily exposure limit value 5 m/s2 A(8)
� Daily exposure action value 2.5 m/s2 A(8)
Exposure likely to be above action value?
– Action plan to reduce exposure and start
health surveillance
Exposure above limit value?
– Immediate action
Suspect any process that causes tingling or numbness after 5 - 10
minutes continuous use.
Assess
�Magnitude of vibration
�Duration – trigger time
Interactive exposure spreadsheet on
HSE website
Points system to assess exposure
•All values are exposure
points
•Colours show exposures re.
EAV & ELV
Manufacturers data
� manufacturers are now working to new Standard tests written to address the requirements of the Supply of Machinery (Safety) Regulations 2008
� new Standard tests are intended both to facilitate comparison of the vibration emissions of different models of equipment and to be suitable for initial estimates of exposure.
� You will still need to check with the manufacturer that the vibration emission declared in the instruction manual is representative of your normal use of the equipment.
CONTROL
� AT SOURCE
� Selection of work equipment: maintenance: positive purchasing policyLimit daily exposure: Job rotation: warm clothing
� Anti Vibration gloves “they are not particularly effective at reducing the frequency-weighted vibration associatedwith risk of HAVS and they can increase the vibration at some frequencies” (HSE website)
Reduce
exposure time
e.g.
•Automate
•Rotate
•Regular breaks
Reduce
vibration e.g.
•Mechanise
•Rigs, jigs & clamps
•Lower emission equipment
�Correct selection of equipment
�Correct operation of equipment -– especially
important with some vibration-reduced designs
�How to recognise (and report) symptoms of HAVS
�How to minimise risk (exercising fingers, keeping
warm, breaks from exposure, not smoking, etc.)
Information, instruction andtraining for operators
� Example – vibration reduced
breaker:
1. Keep the moil point sharp
2. Break a little at a time,
3. Don’t get jammed
4. Don’t force antivibration
5. handles
6. Stop breaker before pulling out
Operator training
Control – tool selection
• Vibration can be very
different between
tools
• An under-powered or
inefficient tool can
increase vibration
exposure
Tool selection – the balance
Larger tool
•Increased vibration emissions
•Increased stress on hands/arms
Smaller tool
•increased grip force
•increased exposure to
vibration
Control – keep hands warm
Temperature Problems
Air exhausts can cool operators' hands
which makes them more susceptible to
the effects of vibration. Cold handles
can also produce a similar effect.
Solutions
Scrap tubing and an old gauntlet were
used to direct exhaust air away
from the hands. Rubber sleeving can
also be used as insulation on metal
handles to keep hands warmer.
Control – tool selection
Vibration magnitude in m/s2
Time before daily exposure exceeds2.8 m/s2 A(8)
Daily exposure time
Daily exposure(m/s2 A(8))
Traditional
breaker design
(typical)
12 26 minutes 3 hours 7.3
New breaker
design
8 1 hour 3 hours 5
Control – maintenance chainsaw
anti-vibration rubber bushes
Control - maintenance
Vibration magnitude in m/s2
Time before daily exposure exceeds 2.8 m/s2 A(8)
Daily exposure time
Daily exposure(m/s2 A(8))
Before 9.7 40
minutes
2 hours 4.8
after 5.4 2 hours 2 hours 2.7
Control -Mechanisation removes the risk
� Machine-mounted pick replaces hand-operated breakers
Control
Removing defects in steel castings using a chipping hammer.
Sleeves cost approximately £5 each.
Control - rig / jig
Control - Demolition without vibration
� Use hydraulic crushers instead of demolition hammers
Control - power tools purchasing
policy
The cost
� Minimal as tools would be replaced at the end of their life anyway.
Control – purchasing policy
Vibration magnitude in m/s2
Time before daily exposure exceeds2.8 m/s2 A(8)
Daily exposure time
Daily exposure(m/s2 A(8))
Oldstrimmer
15 17 minutes 4 hours 11
New strimmer 4 4 hours 4 hours 2.8
Health surveillance
is vital to detect and respond to early signs of damage
Health surveillance is there to:
• Identify new employees whose health
may place them at greater risk,
• Protect existing employees from further
harm,
• Allow employers to identify how effective
their control measures are.
Health surveillance - when
HAVS
• Regular exposure above 2.5 m s-2 (A8)
• Irregular exposure above 2.5 m s-2 (A8)
but frequency and severity is a risk
• When Individuals already diagnosed
with HAVS
Health surveillance
•Important for HAVS because:
– Some high exposures may
be unavoidable
– there is no effective personal
protective equipment
Health surveillance - how
Tiers• Tier 1 Pre-exposure baseline
• Tier 2 Annual screening
• Tier 3 Clinical assessment
• Tier 4 Formal diagnosis
• Tier 5 Optional tests
How can I arrange health surveillance?
� Basic health surveillance consists of regularly seeking information about early symptoms of ill health by using a questionnaire. It may help you keep costs down if you carry out this function yourself, referring any positive responses to an occupational health service provider.
� Alternatively, you could ask an occupational health service provider to provide a complete service on your behalf. You should be able to find details of occupational health service providers from your trade association, your local telephone directory, the internet or EMAS
Further Information on Health surveillance
Health surveillance for HAVS – guidance for employers
Health surveillance for HAVS – guidance for Occupational Health Professionals
Health Surveillance QuestionnairesInitial screening questionnaire
Annual screening questionnaire
Clinical questionnaire
Further information - HSE
www.hse.gov.uk/vibration
Further information
Manufacturers handbook
Databases
� www.las-bb.de/karla/index_.htm� http://vibration.arbetslivinstitutet.se/eng/havhome.laso
o
� www.hse.gov.uk� www.operc.com
ANY QUESTIONS?