Lloyds Environmental Waste Management Ltd was formed in April 1993 as a liquid waste tankering company. Since then they have become one of the leading waste management and drainage specialists in the UK boasting a blue chip customer base right across the country. During this time, the organisation has also become a specialist oil and chemical spill responder and offers an emergency response service 24 hours a day, 365 days a year.
Lloyds Environmental Waste Management has been involved in various activities which require the use of breathing apparatus for over ten years. These activities include drain and sewer cleansing, CCTV surveying and tank cleaning. An integral part of this work is confined space entry. Working within confined spaces is a hazardous occupation and precautions must be taken to ensure that a safe system of work is in place.
To ensure that a safe system of work is employed it is essential that the following steps are undertaken:
Reference to the “Confined space regulations 1997” is essential when undertaking this type of work.
For the purposes of this article detailed examination of the process of risk assessment will not be discussed. For work in confined spaces it is necessary to undertake a risk assessment. This document should consider such matters as access and egress; contents or previous contents of the space; are there any inlets to the space e.g. storm drains running in, etc. If there is an unacceptable risk despite any conceivable precaution, manned entry should not be permitted. After the risk assessment has been completed then further planning can proceed by producing the method statement.
Firstly the basic principles of health and safety i.e. information, instruction, training and supervision should always be considered. The method statement for the job is very useful because it details how a job is to be done, what is required both in terms of personnel and equipment and the scope of the works. This document is to be used to brief the workers prior to commencement of the job and for reference whilst on site.
Selection of personnel to do the job
If confined space entry is required, by its very nature there will be restricted room for manoeuvre. Choose the operative who is physically able to work in such spaces. There is no point sending a person who is either too wide in girth or too tall in height. In some cases (for example the sewers in Brighton) there are doors that open into a sewer system that are large enough for several people to stand side by side. The converse can also true; the space can be small so that the operative has to work on hands and knees.
The standard of health of staff entering confined spaces and using the necessary equipment is an important consideration. Smokers often suffer from shortness of breath; obviously asthma sufferers would not be suitable to work in such an environment and use self contained breathing apparatus as a safety device. In short, staff need to be physically fit to be able to carry out assigned tasks. Staff must be selected not only on their intellectual abilities but also their physical attributes to ensure that they are capable.
Training of staff must be carried out by experienced and approved training providers. There are many companies providing such training but it must be appropriate to your individual requirements. Of the many training providers, Lloyds Environmental have used Pivotal (formerly ESS Shorco Training) and Southern Safety Consultants. Pivotal is one of the UK’s leading providers of organisation wide training programmes offering high quality practical courses at venues across the UK.
Employing over 150 people and with branches in Wellingborough, Leeds, Brentwood, and Glasgow, the business is rapidly becoming one of the foremost names in the provision of safety training especially in the fields of confined space and working at heights. Southern Safety Consultants are based in Fareham, Hampshire in the UK and again have many years working with breathing apparatus, providing training and servicing of equipment. Both companies offer flexible options which have suited Lloyds’ requirements.
When it’s time to go in
For basic confined space entry with escape sets it is recommended that at least two people work together. For example, with entry into a septic tank to carry out a minor repair, an operative should work with a “top man” to enter the tank. For more complex operations more personnel would be required. All operatives engaged in such work need to have undergone formal training. Some companies working in the sewerage industry do not train the “top man”, however it is important for the top man to understand what is going on below, what is required for entry and what he needs to do in the event of an emergency.
Reference to the Water UK occasional guidance note for the “The classification and management of confined space entries”, first issue January 2004 is beneficial when planning more complex tasks involving full breathing apparatus and multiple crews.
Which type of respiratory protective equipment is most suitable? Are self contained breathing apparatus or 10 minute escape sets required? Can a continuous air flow system be employed? When deciding on the type of breathing equipment to be used again the conditions of the job in hand need to be thought through. Is there room for extra air lines running through the access to the confined space? Can the operative climb through the manhole with a gas cylinder on his back? Can the operative exit the confined space easily without encumbrance?
The face masks of the breathing apparatus need to be fitted to the individual wearer. Those with facial hair present difficulties with providing a good seal to the face. Hoods for escape sets may be an alternative to the full face mask.
Prior to entry into any confined space a “permit to enter” should be completed. This permit includes: detail on the site location, client, date and time for which the permit is valid for; an assessment of the risks on the site; what equipment is required; any equipment to be isolated; initial gas readings (this list is not exclusive and should be tailor made to suit individual requirements).
If confined space entry with escape sets is to be used, restricting staff to maximum working time in the chamber and then rotating staff is recommended. Working in a restricted space can be cramped and operatives are often subjected to elevated temperatures. Rotating staff will enable more efficient working and allow individuals to rest and cool down if environment is above ambient.
When working with self contained breathing apparatus a “tally” system should be employed. This will allow the top man to log entry times of the crew and monitor how much time has been spent working using the BA. The maximum working time should allow for the safe exiting of the operatives with air to spare. Although consumption rates will vary from person to person, a safety contingency should be built into the working method to avoid anyone exhausting their air supply. The top man should be in constant communication with the crew using the BA. A clear emergency action plan must be in place prior to commencement of works should an accident occur. Notification of the works to the emergency services would be a sensible precaution.
Proper maintenance is essential
Any breathing apparatus which is used for confined space working needs to be serviced at regular intervals, as should all the equipment for these applications. Consult manufacturers for the recommended frequency. Face masks need to be fitted to the individual wearer and kept for their sole use. Facial hair will affect the seal of the mask to the face.
The supervisor should be checking personnel and the suitability of the kit. Some people may favour the use of a hood rather than a full face mask for their escape set. With a hood facial hair does not affect the seal around the face. Gas cylinders are normally made of steel or light weight carbon fibre, although the latter are more expensive. All cylinders need to be tested at least every five years.
Gas monitors will need to be calibrated at regular frequencies. Any items which show wear and tear or are out of date on service or calibration should be removed from use. Service and calibration records should be kept. Gas monitors commonly available are able to monitor a number of different gases. For normal sewer work a three gas monitor with oxygen, methane and hydrogen sulphide sensors would be appropriate. A wide variety of sensors are available, for example Carbon Monoxide, Sulphur dioxide, ammonia, etc. The risk assessment and job specification would highlight the need to select the correct sensor for the job.
Safety harnesses should be used and, if possible, individuals should have their own. This will enable the harness to be adjusted to that individual thus saving time when putting it on. Harnesses should be inspected by a competent person to detect any damage or frayed webbing on a regular basis.
A tripod and fall arrest system may be necessary. The tripod can be positioned over an open manhole with the fall arrest safety line attached to the harness. A tripod will be rated to a maximum permissible weight. In the authors own experience, it is possible that some operatives will exceed that weight. Do check!
The fall arrester is designed to stop free fall of an operative if they loose their footing when entering a chamber. Some operatives find that the fall arrest is a nuisance and are tempted to work without it. This should under no circumstances be allowed to happen. This line enables the rescue of any operatives who come into difficulties. The top man will be able to winch their colleague back up to safety. Is the length of safety line long enough? For example, if you are emptying a septic tank followed by manned entry to wash it down, it is possible to have suction hose, a water jetting hose plus the safety line all of which are liable to be tangled up together. The top man should be able to prevent this from happening.
Many of these questions should be answered when a detailed risk assessment is done. Some Companies use a generic risk assessment but it may be necessary to perform site specific risk assessments to determine hazards and risk unique to the job. A competent person to undertake the risk assessments is a must, someone with a thorough knowledge and understanding of the hazards and risk involved. When compiling a risk assessment it is possible to conclude that taking on a particular job presents an unacceptable risk; therefore refusal to do the job is the only option. Don’t be afraid to say No!
A method statement will be necessary to detail step by step instructions on how the job is to be done by the crew. A structure to this document is useful, as is initial preparation prior to departure from the yard. This will include checking of all the equipment. Does the gas monitor have a fully charged battery? Frequent problems encountered are either the gas monitor not working due to a low battery or finding that the air cylinder is empty or low. Both cases are potentially fatal for the people using the equipment.
All the equipment, on being returned to the store on completion of the work, should be inspected and cleaned. This may go as far as being serviced if necessary so that when any of the equipment is next used it is ready and available. Any faulty equipment is removed from use.
Working within confined spaces and using escape breathing apparatus or self contained breathing apparatus can be performed safely if it is carefully planned and supervised, using trained personnel with the correctly maintained equipment.
Published: 01st Apr 2005 in Health and Safety International