Withdrawn Document Uncontrolled When Printed CE/CESM CESM - USE OF BITUMEN PART F.9

Transcription

1 CE/CESM CESM - USE OF BITUMEN BOILERS PART F.9

2 ~ Britkh Rail CIVIL ENGINEERING SAFETY MANUAL Sheet 1 of 5 This CESM Part supersedes that of FEB 1988 and contains the following Sections: 9.1 Introduction 9.2 Hazards 9.3 Preparation and Handling 9.4 Action in the Event of Fire or Overheating 9.5 Personal Protective Clothing 9.6 Further Advice 9.1 INTRODUCTION (a) This CESM Part deals with the safe use of bitumen boilers, the hazards and fire risks involved, the safety precautions in the preparation and handling of hot bitumen and the personal protective clothing to be used. (b) When work is carried out by Contract, the Contractor has the responsibility of ensuring a safe system of work. The Board s representative controlling the work must however ask the Contractor to demonstrate that all safety requirements have been met. (c) For First-Aid arrangements see CESM Part A.1O HAZARDS The most obvious hazards when using bitumen boilers eye injuries and fire. Less obvious are the health of prolonged skin contact with bitumen and from the fumes. are those from burns, hazards arising out inhalation of toxic (a) Burns are commonly suffered when: (b) Blocks of bitumen are dropped into the boiler. Hot bitumen is ladled. Hot bitumen is handled and transported to the place of work. Water from ladles, cans, buckets, etc mixes with hot bitumen and explodes. Contact is made with the boiler, burner, ladle, etc. The boiler containing hot bitumen is moved. Flashover takes place between burner and hot bitumen. Eve Iniuries are usually severe and the damage is irreversible and permanent. They are caused by splashes of hot bitumen or flying particles or splinters when blocks of cold bitumen are broken up. The risk of eye injuries will be greatly minimised by the continual wearing of suitable eye protection during the work process. (See 9.5). (c) Fire can be caused from: - Excessive heating of bitumen. Bitumen overflowing onto the burner. Faulty LPG equipment andlor installation. 3015/7674k/43

3 Sheet 2 of HAZARDS (CONTD) (d) Skin tissue is damaged if bitumen is allowed to remain in prolonged contact with the body. The bitumen acts as an irritant, eventually leading to the formation of warts that may turn malignant. See HSE S Card Skin Cancer Caused by Oil MS(B)5. Skin contact may be prevented by the use of protective clothing covering the arms and legs. The risk of damage to the skin is also minimised by washing at the end of each work period and by regular laundering of contaminated clothing. Splashes of bitumen on the skin should be treated promptly with cold water and not wiped off while still hot. When bitumen has set, it can be removed by flexing and gentle scraping. I (e) Toxic Fumes present no hazards in open air or in well ventilated conditions if they are rapidly dispersed and if the bitumen is heated to the correct temperature. In such conditions respiratory protection is not required, but if fumes are a nuisance, a respirator should be worn. (See CESM Part H.5). 9.3 PREPARATION AND HANDLING (a) Settina up the work (i) (ii) When heating bitumen, the boiler must always be in view of the operatives or an attendant must be provided. The boiler must be located away from persons not involved in the work and from other work processes. Where possible it should be sited downwind of the place of work and at ground level, the boiler standing on wet sand or in a metal tray. The sand should not be allowed to dry out during the work. (iii) When used at roof level the boiler must always be stood in a metal tray. (iv) (v) The tray must be level and the boiler set in the centre of the tray so that spillage is contained. The setting up of the gas cylinder must be in accordance with BR 12323/6 Liquefied Petroleum Gases Safety Precautions. In addition, the following procedure must be followed: - Stand the cylinder securely in an upright position at least 3 metres from the boiler, taking adequate precautions to minimise the possibility of persons tripping over the hose. Before assembly, examine the hose to ensure that it is sound and that fittings are in good condition. - Connect the armoured hose to the valve and burner using the spanner provided for tightening. Finger tight connections are not sufficient. Check that all appliance cocks and valves are fully closed. 3015/7674k/44

4 Sheet 3 of PREPARATION AND HANDLING (a) Setting UP the work (Contd) - Turn on the gas and test joints for leaks using soapy water. - 2 No. 5.5 litre AFFF Fire Extinguishers should be provided and kept readily available for use at all times. (b) Prep aration of bitumen boiler (i) Ensure that the boiler is free of water or any other extraneous material. (ii) Keep the lid in position at all times, except when ladling out, replenishing or cleaning out the boiler. (iii) Light the burner on a low setting BEFORE inserting it into the boiler casing. While the burner remains alight, ensure that the vent hole at the rear of the boiler is kept open to avoid the possibility of blow back. (iv) Adjust the gaslair mixture if required by means of the square nut at the end of the burner inlet until the flame is blue. (v) Insert the burner into the boiler casing using the rod provided. (c) Heatina of bitumen (i) Place a small amount of bitumen in the boiler and turn up the gas setting. The bitumen must be allowed to melt gradually, more being added until there is a sufficient quantity for the job, ensuring that the boiler is never more than three quarters full. (ii) The working temperature of bitumen is slightly above that of boiling water. When this temperature is reached, a small amount of off-white fume rises from the surface which does not obstruct the operative s view of the bitumen. (iii) In the early stages of heating bitumen, overheating can cause a rapid expansion of bitumen at the bottom of the boiler. This pushes the cold core of bitumen to the surface causing the hot bitumen to escape under pressure and spray the surrounding area. (iv) BITUMEN MUST NOT BE ALLOWED TO BOIL (v) Care must be taken when the ladle is lowered into or removed from very hot bitumen as spontaneous combustion can take place when cooler air around the ladle enters the boiler. 3015/7674k/45

5 Sheet 4 of PREPARATION AND HANDLING (c) Heating of Bitumen (Contd) (vi) Use the ladle to transfer hot bitumen to a pouring can or bucket, ensuring that the can or bucket is not more than three quarters full, being particularly careful during windy conditions. (vii) Carefully replace the amount of hot bitumen removed from the boiler, with manageable pieces of bitumen to prevent splashing. (viii) If the boiler is used for several shifts, it should be left a quarter full at the end of each shift as this will greatly assist in heating up the bitumen evenly at the beginning of the next shift. (ix) During use of the boiler, the presence of sediment may produce oily bubbles and yellowish brown fumes on the molten surface of the bitumen. (x) Whenever the boiler is left unattended, the burner must be extinguished and removed from the boiler. (xi) Ensure the area immediately surrounding the boiler and LPG cylinder is kept clear of combustible material. (d) Completion of the work (i) At the end of each shift, ladles, cans, and buckets should be emptied and stored upside down, preferably under cover. This reduces the possibility of water getting into the containers. (ii) Towards the end of the last shift, the burner should be turned off and all the bitumen used. (iii) When the boiler and sediment is cold, the boiler should be inverted and a piece of wood held on the base of the boiler and struck with a hammer to vibrate the sediment loose. 9.4 ACTION IN THE EVENT OF FIRE OR OVERHEATING (a) Turn off the gas at the cylinder, disconnect and move the cylinder to a safe place. (b) If possible and without endangering oneself, replace the lid and allow to cool. (c) If the bitumen is on fire and it is not possible to replace the lid, use the appropriate fire extinguisher, eg AFFF (BR Cat. 47/27510) or Dry Powder (BR Cat. 47/27973), if safe to do SO. (d) Call the Fire Brigade. (e) Report details to the person in charge. 3015/7674k/46

6 Sheet 5 of PERSONAL PROTECTIVE CLOTHING (a) Overalls - covering body, arms, legs. (b) Gauntlets Type C1 (See CESM Part H.8). (c) Goggles Type 3, 3A, 4, 5 (See CESM Part H.2). 9.6 FURTHER ADVICE may be obtained through normal managerial channels and from Safety Engineers. Signatures removed from electronic version 3 S CORNELL (CEC Min. 91/155 and DoCE letter 12 August 1991 DIRECTOR OF CIVIL ENGINEERING principles apply)