Issue 14: October 2000
Research projects commissioned in the Mainstream S&T Programme culminate, wherever possible, in the production of a published report, documenting the work undertaken during the course of the project, the findings and the conclusions or recommendations drawn.
There are currently two publication series within the Mainstream Science and Technology Programme: Contract Research Reports (CRRs) and Offshore Technology (OT) Reports. A considerable amount of time and effort has been spent on making these reports available via the internet, and a significant proportion of the back-catalogue of CRR and OT reports are now available for free download in portable document format (pdf) from the HSE website at the following address:
www.hse.gov.uk/research/index.htm (under research publications).
Once the complete back-catalogue of CRR and OT reports has been reviewed and the reports placed on the internet, the intention is to place the reports onto the website as they are produced.
Rather than downloading a copy of a report, glossy, hard copies of research reports can still be purchased from HSE Books. The pricing structure has been reviewed, and whereas previously a research report could have cost as much as £175, their cost is now unlikely to exceed £40.
HSE's Health and Safety Laboratories (HSL) are reviewing their back-catalogue of HSE project reports with a view to placing these on the internet. Once this suite of reports is uploaded it is intended to introduce a single publication stream encompassing reports that would have become either CRR, OT or HSL reports.
THE EVALUATION OF OCCUPATIONAL HEALTH ADVICE IN PRIMARY HEALTH CARE
(Contractor: Institute of Occupational Health, University of Birmingham)
Changes in the British economy have led to a significant increase in the proportion of workers employed in small enterprises and a corresponding decrease in the number of workers with ready access to occupational health support and advice. Such workers often have no alternative but to seek advice from their GP, who may not have sufficient resource or expertise to deal with the issue. Occupational health advisers working in seven city Occupational Health Projects (in Sheffield, Rotherham, London, Lothian, Liverpool, Leeds and Bradford) have been providing an occupational health advisory service to primary care patients (in surgery waiting rooms) for several years. Outcomes include empowerment of the worker to influence better health and safety provision at the workplace and identification of the role of work tasks and activities in the onset of health problems and hence improved diagnosis and treatment. Enough experience of this approach has now been gained to justify its formal evaluation. This project will investigate whether the provision of advice on workplace hazards to people in the primary health care setting results in improvements in their working environment. The project will also examine how such changes in the working environment were achieved and the consequent benefits to the person advised and/or others, or where appropriate, why change could not be achieved.
AVAILABILITY, QUALITY AND STANDARDS OF TRAINING FOR WOODWORKING OPERATORS AND SUPERVISORS
Woodworking is the only remaining industry where employees have to regularly work with machinery where the cutting tools or blades are necessarily exposed. Woodworking machinery causes significantly more major injuries than machinery in any other industry, and during the period 1997/98, the incidence rate for major injuries was 106.7 per 100,000 employed whilst the average across all industry was 35.7. Of particular concern is the statistically significant fact that the total number of reported woodworking machinery accidents is rising. Ill health is also a concern. Workers in this sector report high levels of manual handling injuries, the incidence of which is increasing. Other hazards, such as noise dust and vibration are also present in woodworking premises.
Adequate training is vital for both users of woodworking machinery and their supervisors in order to ensure that safe working practices are followed and that safety and health risks are reduced. The number of colleges offering woodworking training appears to be declining, and HSE has received reports from employers and trade associations that difficulties in procuring woodworking training either on or off-site have been experienced. Industry-lead bodies have indicated that there is poor uptake of available NVQs and that training seems to come primarily from employers in the workplace.
This project aims to examine the availability of suitable training and to establish what training is currently delivered to woodworking machinists and their supervisors, how it is delivered and to what standard. Where standards of training or training arrangements are found to be inadequate, the project will seek to identify ways in which HSE can influence employers and training providers to improve the quality and standard of training provided.
AUTOIGNITION OF GASEOUS HYDROCARBONS NEAR A HOT SURFACE
(Contractor: Shell Global Solutions)
There are many industrial applications where a flammable gas/air mixture can develop near a hot surface, for example: on chemical plants; in petrochemical installations both on and offshore; and in gas turbine halls. Autoignition is a notoriously complex phenomenon. Data are available on the effect of gas volume, surface material composition and other variables, on autoignition temperature (AIT). However, there is little information on the fundamental physics and chemistry of autoignition by hot surfaces. The ignition potential is currently assessed by comparing the surface temperature with the AIT of the gas mixture. However, the reported AIT can vary by several hundred 0C for a given mixture in more realistic geometries. Current methods used to assess the ignition potential of hot surfaces may thus be unduly conservative.
The contractor has carried out work previously to investigate hot surface ignition and has developed a unique chemical kinetics/computational fluid dynamics code to model the fundamental physics and chemistry of autoignition by hot surfaces. The aim of this project is to carry out a series of additional experiments to look at the autoignition of methane by hot surfaces. These results will then be used to further develop, calibrate and verify the performance of the existing computer model.
EPIDEMIOLOGICAL EVIDENCE FOR THE EFFECTIVENESS OF THE NOISE AT WORK REGULATIONS
(Contractor: University of Southampton)
The Noise at Work Regulations 1989 are integrated within a substantial framework of regulatory provisions which apply in the UK with an aim of preventing noise induced hearing loss (NIHL). The extent to which these provisions are effective in preventing the development of NIHL is difficult to establish. This is partly due to the long latency period before damage of NIHL becomes apparent using traditional methods of detection, but also because there is no statutory requirement to report cases of NIHL.
NIHL involves a loss of outer hair cell function within the cochlea in the ear. Health surveillance for noise exposed workers is required under the Management of the Health and Safety at Work Regulations 1992, and occupational audiometry does provide an indication of damage to hearing resulting from exposure to noise. However, the varying quality of audiometric assessments, the subjective nature of the test and inherent methodological difficulties make it difficult to assess the effectiveness of the regulatory framework using this methodology alone, particularly in the short term.
The emergence of techniques to evoke otoacoustic emissions has enabled non-invasive, objective and fast assessment of cochlea function. There is evidence that otoacoustic emissions are sensitive to the early stages of cochlea dysfunction as indicated by a reduced mechanical responsiveness of the cochlea to sound. The use of this objective measurement technique, together with assessment of compliance to the Regulations by employers, in a longitudinal study of young workers entering noise and non-noise exposed workforces has the potential to enable evaluation of the effectiveness of the Noise at Work Regulations. This project aims to establish whether young workers entering employment in noisy industries experience decrement in their hearing level, greater than that of workers entering jobs with no noise exposure.
DECOMMISSIONING AND REMOVAL OF CONCRETE GRAVITY STRUCTURES IN THE UK CONTINENTAL SHELF (UKCS)
(Contractor: WS Atkins Consultants)
Of the nine concrete gravity structures installed in the British sector of the North Sea, several were designed and constructed almost 25 years ago. At that time, little attention was given to any eventual need to remove these structures. Existing evidence suggests that a number of these structures may be unable to retain sufficient structural integrity (during attempts to re-ballast and refloat them) to allow their safe removal. However, although safe removal of the whole structures could be unlikely, it still may be reasonably practicable to remove the upper parts (towers) to a depth of around 75 metres to provide as much clearance as possible below the still water level. The aim of this Joint Industry Project is to assess the feasibility of partial removal of concrete gravity structures in the UKCS from the seabed after decommissioning, in a safe and environmentally acceptable manner.
CRANE INFORMATION DATA PROJECT
(Contractor: A1 Safety Training Consultants 1995)
The aim of this project is to provide a crane information database, containing major technical information and incident data for every offshore pedestal crane currently operating in the UK sector of the North Sea. This currently involves approximately 600 cranes on fixed installations and a further 180 on mobile installations. Because of the numbers of cranes involved, there is great variation in their type, design, operational capability, incident history and modification record across the sector. The project will produce a comprehensive record for each crane and a methodology for maintaining the currency of the information, reflecting both changes which may occur to the actual cranes themselves and the changing locations of mobile installations.
The information will enable HSE inspectors to better target their inspections and audits in this particular area and will help to improve efficiency when they are visiting duty holders' offshore installations.
META ANALYSIS: IMPACT OF WORK-RELATED STRESS ON HEALTH
Some previous research has suggested that recent changes in working practices (new ways of working) may have implications for the physical and mental health of employees.
The potential problems identified are global, but some may be more prevalent in the UK. In particular, there is evidence that the UK has developed a culture of long working hours. The existing literature on the health impact of these workplace changes is large, disparate and often contradictory, and although some underlying trends have been identified, it is unclear as to whether HSE is justified in acting on them. There is a clear need for the research to be rigorously reviewed and summarised. The findings from such an exercise have the potential to inform and focus future research and practice in this area. This project will involve a comprehensive search of the published literature from around the world. Those articles suitable for meta analysis will then be selected using standardised criteria. A series of meta analyses will then be undertaken to collate and summarise the relationships between physical and mental well being and each of the following: working hours; job satisfaction; management style; job control and job security.
EXAMPLES OF RECENTLY COMPLETED PROJECTS
EFFICACY OF WATER DELUGE AGAINST BUTANE JET FIRES
(Contractor: Shell Global Solutions (UK))
Liquefied Petroleum Gas (LPG) storage tanks are provided with water sprays, referred to as water deluge, to protect them in the event of a fire. This protection has been shown to be effective against pool fires, but uncertainties remained regarding the degree of protection provided from a jet fire caused by liquid or two-phase release of LPG.
In 1996, a HSE-funded project was undertaken to study, at full scale, the performance of a water spray system in protecting an empty 13 tonne LPG vessel subjected to jet fire impingement from liquid propane. The results, reported in Contract Research Report (CRR) 137/97, showed that the typical water deluge system found on an LPG storage tank cannot be relied upon to maintain a water film over the whole vessel surface in an impinging propane jet fire scenario.
The aim of this subsequent work was to extend the existing knowledge to include the effects of butane jet fire impingement on an LPG vessel. Butane jet fires were known to have different characteristics and consequently may result in different conclusions to those already drawn for propane. Twenty butane jet fire impingement tests were carried out, which provided a direct comparison with the propane tests in the earlier work. The results were in fact similar. Water deluge did not always prevent dry patches appearing along the top of the LPG vessel, although the patches were generally smaller than those seen during the propane jet fire tests. The water deluge had similar effects on the butane jet fire as those seen for propane. Luminocity and smoke were reduced and a lower rate of wall temperature rise at the dry patches was produced when compared to a jet fire-impinged, undeluged vessel. A butane jet fire impingment test was repeated with a longer duration of 10 minutes, at which time the maximum temperature of the small dry patch had stabilised at 360oC. A final test was performed with a duration of 20 minutes. One of the water nozzles was blocked to produce a larger dry patch. The maximum temperature of this patch stabilised at 580oC. At this temperature the steel wall of the LPG vessel would be severely weakened, but may not necessarily fail.
The results from this work will be published in HSE's CRR series.
STABILITY CHARACTERISTICS OF 3- AND 4-WHEELED VEHICLES
(Contractor: Frazer-Nash Consultancy Ltd)
The incidence of forklift and dumper truck rollover has been a source of concern for sometime, as death or severe injuries of the drivers can occur as they try to escape their rolling vehicle. Previous research has already examined the baseline stability of industrial and agricultural machinery, but the rate at which a vehicle rolls had not already been considered. This study, a successful bid in HSE's Competition of Ideas exercise, was conducted in three phases. A comprehensive literature search was undertaken, the results of which were used to aid development of a technique to predict the forward speed and rate a given vehicle will roll and the duration of a roll 'event'. The technique was developed using an advanced programming language (IDL), based on a true dynamic, real time simulation. Where possible, the methodology was simplified into an Excel spreadsheet format. This was found to provide results consistently within 5% of those predicted by the IDL version. Several types of forklift and dumper truck have been assessed and a parametric study has been carried out to consider the variation of geometrical and mechanical parameters and the effects these changes have on vehicle performance. The results of this work will be published in HSE's CRR series
PROTECTIVE CLOTHING IN POTTERIES
(Contractor: University of Leeds)
Evaluation of performance (dust protection, wear and comfort) was carried out on two polyester fabrics used to make protective clothing for pottery workers. The most commonly used fabric had good abrasion resistance, high tear and tensile strength and moderate moisture vapour transmission (MVT), but was uncomfortable to wear. Before use, the fabric had acceptable dust protection properties. After a few laundering cycles the particle exclusion efficiency deteriorated, compromising protection.
Six alternative fabrics from a group of 22 were chosen with the aim of recommending a replacement for the current fabric. All had much improved dust exclusion properties, especially after laundering, as well as better MVT values. The group of chosen fabrics contained examples of polyamide/polyester tightly woven fabrics, and both hydrophilic and microporous-coated tightly woven polyamide based fibres. In factory trials, all fabrics provided improved comfort in comparison to the current fabric. An effective method was established for the testing of comfort within the clothing microclimate of the worker. Temperature and relative humidity sensors, together with datalogging devices, were employed to record data throughout the working day. Parameters evaluated for the measurement of comfort, particularly water vapour concentration both within and outside the clothing microclimate, were compared with subjective tests. The most effective fabrics were determined and recommendations for replacement fabrics made. A comprehensive assessment of male and female style overalls was also undertaken and an improved design was proposed to provide greater comfort and practicability.
MANAGING POST INCIDENT TRAUMA IN THE UK POLICE FORCE
(Contractor: Glasgow Caledonian University)
This study aimed to assess the incidence and effects of post trauma reactions to critical incidents in two police services: Strathclyde and the Royal Ulster Constabulary. The study compared the experience of traumatic reactions across these two different policing contexts and examined aspects of the person and their working environment that may influence the way critical incidents are coped with. The study also aimed to look at how UK police organisations protect officers from the effects of critical incidents.
Strathclyde group - questionnaires were sent out to 1245 officers (612 returned) ranging in rank from above probationer to chief inspector. Occupational groups studied included officers in traffic, mobile and foot patrol, authorised firearm, the female and child unit, CID, scenes of crime unit and support unit. RUC group - questionnaires were sent to 1600 officers (768 returned) in the same ranks and groups as the Strathclyde group, with the exception of the inclusion of superintendents in the RUC group.
The results highlighted the incidence and effects of critical incidents. When a critical incident is placed in the context of other dissatisfactions within the workplace, this more demanding aspect of police work can be overwhelming. In such cases it is important that sensitive support is offered. The approach of the supervisor to the officer after the incident is crucial to the way it is managed. Supportive supervision is essential. Critical incidents can lead to chronic psychological distress, the use of poor coping strategies and alienation from family and colleagues. Such problems may be overcome by encouraging officers to take care of themselves both psychologically and emotionally.
The report will be published in HSE's CRR series
ASSESSMENT OF A CONTINUOUS MINER 'WET HEAD' SYSTEM
(Contractor: IMC Technical Services Ltd)
Continuous miners have been in use in the UK for many years, although until the late 1980's only in limited numbers and mostly in the coalfields of North East England. However, with the general introduction of roofbolting as the primary means of roadway support in most UK collieries, and the consequent adoption of rectangular section roadways, use of continuous miner type machines has increased significantly. Because these machines are now operating within mixed coal and stone strata (sometimes including hard sandstone) the newer continuous miner machines are much more powerful. As a consequence, environmental control with respect to the prevention of frictional ignitions of methane and control of dust on continuous miners have become a cause for concern. In the five year period to 1999, continuous miners were responsible for 3 of the 6 incidents of frictional ignition associated with cutting in UK coal mines.
Wet cutting techniques are in common use on most mining machines, being acknowledged to be the most efficient means of dust control while also being able to reduce the probability of frictional ignition. However, potentially reliable wet cutting systems have only recently been developed for continuous miners and the objective of this project was to assess the practical application and implications of wet cutting systems for continuous miners working in the UK.
Surface trials carried out on one system demonstrated that it could provide both effective ventilation of the cutting zone and quenching of hot ignition sources from cutter picks, thereby preventing frictional ignitions in addition to dust suppression. The system had phased water outlet, where only the active two thirds of the total number of pick sprays were operated at any one instant. Even so, a total water flow of approximately 80 litres/min was require to achieve full benefit from the system. This water requirement is 3 to 4 times that normally used on machines in the UK and is liable to present operational difficulties at many sites. Specific benefits may be achievable with half this volume of water either for dust control by using each alternate spray, or for ignition prevention, by targeting particular high ignition risk areas of the cutter drum.
- CRR 269 - Flue Performance of Domestic Gas Burning Appliances. Aim 1: Full-scale Test House Measurements of the Flue Performance of Open-flued Gas Fired Appliances.
- CRR 270 - Flue Performance of Domestic Gas Burning Appliances. Aim 2: Wind Tunnel Tests on various Model Building Configurations for Safe Flue Installation.
- CRR 271 - Flue Performance of Domestic Gas Burning Appliances. Aim 3: Investigation into the Performance of Extractive Flue Terminals
- CRR 272 - Evaluation of the Good Health is Good Business Campaign
- CRR 274 - Incidence of Virtual Reality Induced Symptoms and Effects (VRISE) in Desktop and Protection Screen Display Systems
- CRR 275 - Assessment of the Validity of Current Dense Gas Dispersion Models at Low Wind Speeds
- CRR 276 - Guidelines for the Inclusion of Low Wind Speed Conditions into Risk Assessments
- CRR 277 - Review of RELEASE Rainout Model and CCPS Data
- CRR 278 - Characteristics of People Working with Chemical Products in Small Firms
- CRR 279 - Feasibility of Developing a Simple Prototype Decision Aid for Initial Medical Assessment of Work Related Upper Limb Disorders (WRULDs)
- CRR 280 - Development and Evaluation of Diagnostic Support Aids for Upper Limb Disorders
- CRR 283 - Risk Perception of Sheep Dippers
- CRR 284 - Survey of the Recruitment Agencies Industry
- CRR 285 - Thermal Radiation Criteria For Vulnerable Populations
- OTN 2000 002 - Fracture Capacity of X65 Pipeline Girth welds Subjected to Deformation Controlled Loading
- OTN 2000 008 - Linepipe Specification for Deepwater Pipelines
- OTN 2000 009 - Calibration of Capacity Equations for Corroded Pipes
- OTN 2000 010 - Design Guidelines for Deep Water Pipelines
- OTN 2000 011 - Design Handbook for Deep Water Pipelines
- OTN 2000 030 - Investigation of the Effect of Test Variables on Hydrogen Permeation due to Corrosion in Sour Environments
- OTN 2000 034 - Assessment of Subsea Pipeline Spans
- OTO 1999 026 - Offshore Structural Components for Reliability Analysis - A Pilot Study on the Rationalisation of g(.) Functions
- OTO 1999 058 - Fatigue Design Curves for Welded Joints in Air and Seawater under Variable Amplitude Loading
- OTO 1999 092 - Human Factors Assessment of Safety Critical Tasks - 1999
- OTO 2000 007 - Pile Load Testing Performed for HSE. Cyclic Loading Study at Dunkirk, France. Volume 2
- OTO 2000 008 - Pile Load Testing Performed for HSE. Cyclic Loading Study at Dunkirk, France. Volume 1
- OTO 2000 015 - Evaluation of Diverless IRM for Subsea Completions and Deepsea Structures
- OTO 2000 026 - Appraisal of API RP2 FPS (Recommended Practice for Floating Production Systems)
- OTO 2000 035 - A Review of Degradation of Firewater Piping and Nozzle Performance due to Blockage
- OTO 2000 037 - A Review of Reliability Considerations for Fixed Offshore Platforms
- OTO 2000 038 - Development of a Structural Reliability Framework for Offshore Platforms
- OTO 2000 039 - Offshore Application and Sensitivity Study
- OTO 2000 040 - Structural System Reliability Framework for Fixed Offshore Structures - Summary Report
- OTO 2000 050 - Application of System Reliability for Offshore Structures
- OTO 2000 052 - Fatigue Reliability of Old Semi Submersibles
- OTO 2000 054 - Digit Database (Version 1) - User Manual
- OTO 2000 056 - FPSO's Lessons Learned
- OTO 2000 059 - Investigations into the Stability of an Intact and Damaged Jack-Up during a Wet Tow: Model Test Interpretation and Assessment
- OTO 2000 064 - Wire Rope Non-Destructive Testing - Survey of Instrument Manufacturers
- OTO 2000 069 - Resin-Socketed Termination of Offshore Wire Ropes
- OTO 2000 074 - Noise Exposure Limits Under Hyperbaric Conditions
- OTO 2000 075 - Factors which could Influence Diver Performance on Neurological Investigation