Building and construction Safety Technology - Assignment Example

? BUILDING AND CONSTRUCTION SAFETY PRECAUTIONS NUMBER GRADE 8TH FEBRUARY Question1. Material Hoist Safety Precaution Safety is a key concern in the construction and design of a material hoist. The hoist must be designed in a manner that it will have the capacity to carry the materials up and have a powerful motor that will not reverse in the process of lifting heavy loads. The lift should be installed in an enclosed construction that connects all the floors of the building with openings at each floor that will act as doors for the hoist. The framework or the chases of the hoist must be adequately strong to avoid destruction when lifting heavy loads (Labor Department 57). The lifts should be maintained regularly and proper records kept after each maintenance session. These are some of the major issues that have been considered in the safety of using a material hoist as discussed below. Workers Training and Safety The construction workers are the people who will be using the hoist frequently, and therefore more likely to be injured by the hoist. To avoid accidents that might be caused by their negligence, it is important for them to be trained on how to use the hoist and some safety precautions. A material hoist should be manually controlled by a well trained operator so as to ensure safety of other workers lacking the technical knowhow of a material hoist operation. All the workers should be provided with a simple list of do’s and don’ts safety information to reduce the risk of self injury due to carelessness. Material Hoist Specifications The material hoist must be designed in such a way that it is enclosed in a compartment which has openings on each floor which will act as doors. Each opening should have a landing plate which will clutch the hoist when loading and offloading (Labor Department 23). The material hoist motor should have a speed governor and an equipment to measure the weight of the load being lifted. The maximum weight to be lifted by the hoist should be effectively communicated to the workers responsible for loading the hoist to avoid overloading. The lubrication of the bearings and gears should be as often as possible to avoid friction and wearing out of joints and wheels. This will also ensure that the hoist motor is not overloaded and reduce the risk of malfunction. The material hoist should be suspended from steel wire ropes of highest possible quality which corresponds with the weight to be lifted. The steel wires should have an allowance for environmental factors such as cold and hot weathers which cause expansion and contraction of the ropes. If overstretched, the ropes may break during cold seasons. A number of steel ropes should be used so that when one breaks others hold the hoist before repair is done (Craighead 210). The minimum diameter of the steel ropes should not be less than 8 millimeters. Other requirements Sound reduction is one of the emerging trends in the field of escalators. The sound of a material hoist should be as low as possible therefore increasing the ability to identify a problem with the hoist when it arises. Sound reducing rubber pads should be installed to eliminate noise and vibrations that might otherwise cause weakening of the beam and the hoist’s frame work. It is recommendable to use stainless steel for the material hoist housing since it has a relatively small weight and yet high capacity of not getting torn apart when lifting heavy loads. Unless stated otherwise, stainless steel should be of EN 10029, EN 10048, EN 10095, EN 10259 or EN 10258 grades 316 or corresponding. Question2. Crane Safety Precautions A crane should be properly maintained and repaired when damaged to avoid its malfunctioning while lifting loads. Before a crane can be employed to lift iron bars, its capacity should be considered. A crane which has a low capacity to lift the weight of the iron bars should not be used; otherwise it may cause injury to those operating it. The hoist rating of the crane should be considered and the weight of the iron bars established (Lafayette 264). Where the hoist rating is unknown, the foreman must find out through all means to avoid overloading the crane which will result to its malfunctioning. The hook of the crane should have a question mark shape. In a situation where it is out of shape, it should be replaced to avoid dropping of the iron bars. The hook should be made of a strong metal (like iron ore) to avoid its loosing shape due to lifting heavy loads. The hook should also be fitted with an adjustable clip which allows chains to be securely gripped. Where the crane uses wire ropes, the ropes should be properly fitted in their grooves. The ropes should be refitted into their grooves whenever they pile upon themselves. Their capacity should match the weight of the iron bars and where the weight of the load happens to be more than the ropes capacity, the crane should not be used. However, the wire ropes can be replaced with ropes of higher capacity provided that hoist rating matches the weight of the load. If the crane is the hydraulic type, the liquid should be kept at the suitable levels as described by the manufacturer. The pipes used for pressure transmission should be well protected from leakages as this will lead to the cranes failure in the middle of lifting a load. The load chain should be in good condition and firmly connected to the hook. There should be no twists on the chain, cracks or rust that may cause the chain to easily break when under tension. The chain should be strong enough so as to lift the iron bars with no risk of breakages (International Labor Office 53). Cranes should be appropriately greased on its joints and rotating parts. This will help reduce friction and also the amount of power required to lift the iron bars. All its bearings should be well maintained and those are worn out replaced before offloading of the iron bars. The crane operator must have the qualifications of working with it. The operator must have met the required experience so that he/she may not be a danger to himself or others. The crane operator also, must possess a license from the concerned authorities showing that he has the credentials necessary. He should have a clean profile in operation of cranes. This shows that the operator is careful since he has not had any accident. Where possible, the foreman should ensure that the crane is inspected regularly and maintained as per the manufactures instructions. Any deficiencies must be corrected before the crane is used (Lafayette 234). No modifications or major repairs should be carried out on a crane unless these are performed by a person competent in this field. Hitches and slings used to hoist materials should be suitable for materials being handled; in this situation, the iron bars. Taglines should be attached to the iron bars so as to be steady while suspended. Question3. Foam Extinguishing Systems Foam is a combination of three effective components which are; water, air and foam concentrate. Water and foam concentrate are combined to create a foam solution specially formulated to put out fires spread by flammable liquids such as petroleum products. When air is added to the solution, the foam creates bubbles which float on liquids that are flammable and cuts out oxygen suppressing the development of the fire (Kidde Fire Fighting 3). Foam fire extinguishers are very effective in putting out forest fires using aircrafts. Foam can be applied in three ways. One is a fixed system in an enclosed room, for example a tank or vault. It may also be an aircraft hangar. In a fixed system, the delivery is essentially a deluge-type sprinkler system. The open heads allow a blanket of foam to be spread over the entire area. The second is a local application system. Here the fixed deluge-type sprinkler equipment is positioned around the area to be protected and the foam is applied in a similar manner over the spot area. The last and most common application is by hand held hose pipe. Foam is sprinkled on the burning areas as it flows from a separate storage container (Fitzgerald 426). There are different types of foams concentrates manufactured from different products and used for different purposes. For example, flouroprotein foam concentrates which is manufactured from hydrolyzed protein, stabilizing agents and preservatives with hydrocarbon surfactants. They have high extinguishing capabilities, flows with ease high resistance to contamination with fuel. This type of foam concentrate is mainly used in the petroleum refineries and plants. Synthetic foam concentrate consists of hydrocarbon surfactants, and they produce foams with high expansion capability. This type of form is most suitable in extinguishing areas which have fire spread on large surface area. Synthetic foam concentrate mainly used in forest fires, warehouses, and large floor areas. Protein foam concentrates is another type of foam manufactured from hydrolyzed protein, stabilizing agents and preservatives. It produces highly stable mechanical foam with good expansion characteristic and high resistance to reigniting. Protein foam concentrates are mainly used in transportation and processing of highly flammable liquids. Aqueous film forming foam concentrates, also known as AFFF manufactured from a mixture of fluoro-surfactants and hydrocarbon surfactants. These are commonly used in by fire brigades, in air ports, refineries and production facilities because of low quality foam. The use of foam to extinguish fires has a number of limitations. If unevenly mixed the foam may form an ignitable mixture since the bubbles of air may support combustion of flammable liquids and gases. There exists a number of foam concentrates which should be used in different situations of fire, therefore some foam concentrates may be ineffective in a given fire situation. For example, Aqueous film forming foam concentrate is totally ineffective in a class “B” fire situation since it has it produces low quality foam and cannot cover a wide area which is ablaze. Foams are totally inappropriate for use in a class “C” fire situation since they are primarily comprised of water, which is electrically conductive. Therefore, foams are not recommended or approved for this application. Foam solution have a shelf life and therefore cannot be effective if unused for a period of 15 years. The solution may also be ineffective if not stored in temperatures of 35 to 120F. Alcohol resistant concentrates are made from water soluble polymers. This enables water soluble fuels such as methanol to be extinguished. This type of form concentrates are mainly used for fire protection when leaded or unleaded petrol is being loaded. Question4. Safety Precautions for Working in a Confined Space A confined space may be any room which has an enclosed characteristic, having a risk of death or serious injury from dangerous substances or conditions. Examples of confined spaces include sewers, enclosed drains, storage tanks, reaction vessels and flour silos. A confined space has a limited or constrained means of entry or exit and working in such situations may be difficult especially where it requires a number of laborers. Tools and equipments may proof to be difficult to use in a confined working space. A number of people are killed or seriously injured in confined working areas. Therefore, there should be a well laid down procedures and rules which will guide the workers to avoid accidents. Key Hazards when Working in a Confined Space There are very many situations and places that can be termed as a confined space. Some places may become confined spaces when work is carried out, or during construction, fabrication or subsequent modification’s number of risks may be present when working in a confined space depending on the space itself. When working in a sewer, the most probable danger a worker is exposed to is lack of oxygen. This happens where the gases produced from the sewer system pollute the oxygen making it difficult for an employee to work in such an environment. This will obviously lead to the death of a worker due to breathing in toxic gases. Employees working in reaction vessels may experience hot conditions which might lead to dangerous increase in body temperature or even burning. There is also a risk of breathing in poisonous gases, fumes and vapor caused by the reaction of chemicals. Storage tanks made of iron may rust becoming a health hazard to people who enter in them since the dust produced may cause health complications. Technical Control Measures for the Confined Space work The safety adviser must carry out an appropriate and satisfactory assessment of the hazard for all work activities involved in a confined space so as to be able to decide on the measures that are necessary for safety. He must consider the task to be carried out, the working environment of the employee, the tools and materials the worker is using, employees’ qualifications and arrangements for emergency rescue (Sargent 124). In confined spaces such as sewers, workers should be provided with gas masks so as to avoid breathing in toxic gases emitted in the sewers. In situations such as reaction vessels, the workers should be provided with protective clothing to shelter them from high temperatures of such areas. Procedural Control Measures for the Confined Space work Reasonable procedures should be followed when working in a confined space. For example, an employee should work from outside where possible and avoid working in confined spaces. It is more safe and logical to weld iron outside a metallic tank than welding it while inside since the worker will be at risk of breathing in more toxic gases. The safety adviser should lay down procedures to be followed when working in confined spaces so as to avoid accidents that are caused by negligence of the employees. There should be proper communication of the procedures to the employees and ensure that they are well trained and experienced to work in confined spaces. Behavioral Control Measures for the Confined Space work The safety adviser must set out rules and procedures which will govern the behavior of the employees working in a confined space. This rules and procedures will ensure that the actions of the employees are controlled to avoid accidents that could have been caused by their negligence. For example, smoking in a reaction vessel should be prohibited since this might lead to an explosion, endangering not only the employees’ life but also those of others. Question5. Metal and Bamboo Scaffoldings Code of Safety A scaffold is a temporally structure which enables people to obtain access to buildings under construction. They act as working platforms, gangways and ladders for workers constructing mainly the exterior of a tall building. A constructor may use either metal or bamboo scaffolding, but they do have their safety requirements and precautions. A code of safety for development, implementation and maintenance of safety and health of workers must be developed to regulate both metal and bamboo scaffolding in order to reduce accidents in areas of construction. For scaffolds to be stable, it is important to consider the ground or supporting structure sufficiency to carry the load imposed on it. The ground on which a scaffold is constructed on should be solid, leveled and rammed to give a hard surface and strong enough to keep the scaffold upright. Metal Scaffolding safety Code In the designing of a metal scaffold, there are a number of considerations that need to be looked at in order to ensure safety all the workers. The erection, alteration and dismantling of a metal scaffolding for all stages of construction should ensure safety. The strength of scaffolding members such as tubes and couplers should be ensured to avoid collapsing. The safety code of using metal scaffolding states that guard-rails should be added at the edges where workers may fall from great heights. The height of top guide-rails should be between 900 and 1150 millimeters above the platform. The height of an intermediate guard-rail should be between 450 and 600 millimeters above the platform and the toe-board shall not be less than 200 millimeters (Hong Kong Labor Dept 46). According to regulation 38H of the CSSR, safety nets and safety belts should be provided to reduce the probability of a worker falling. The workers responsible for designing, erection, maintaining and dismantling scaffolds should be properly trained to increase their efficiency and improve safety performance. All scaffolding components should comply with BS1139 provisions, which states that hot dipped galvanized, painted or unprotected tube may be used in scaffolding structures. Metal scaffolding which is unprotected should not be used in water and marine structures since they will be exposed to rusting which will make them weak. The metal tubes should be free from cracks, splits and excessive corrosion. The safe working loads for individual couplers and fittings should comply with BS5973 which states that joint pins, all couplers and fittings should be free from rust and distortion. Worn out threads and damaged bolts should not be used in setting up scaffoldings. The working platforms should not be allowed to carry more than the set loads. All decking units of working platforms should have adequate strength to meet set standards for the specific duty. Bamboo Scaffolding Safety Code Bamboo scaffolds have been used for construction in Hong Kong for thousands of years. Bamboo scaffolds are commonly used because of their high adaptability, speediness and low construction cost. The statutory provisions in relation to safe bamboo scaffolding under the Factory and Industrial Undertaking Ordinance are discussed below. Section 6B provides that the person employed shall take reasonable care for the safety and health of himself and that of others who may be affected by his acts or omissions at work. Regulation 38A and 38AA specify general provisions for ensuring safety of places of work, safe means of access to from places of work and that no one gains access to places where any dangerous conditions are present (Chow 21). Regulation 38E provides that only trained workmen with adequate experience and under the supervision of a competent person shall erect, change or dismantle scaffolds. Bamboo and metal scaffolds can be used in the same structure therefore making the scaffold stronger and more long lasting. Works Cited Chow, Tin. Development Trends in Building Services Engineering. Hong Kong: City of University of Hong Kong Press. 2009. Press. Craighead, Geoff. High-rise Security and Fire Life Safety. (2nd ed). Woburn: Elsevier Science. 2003. Print. Fitzgerald, Robert. Building Fire Performance Analysis. West Sussex: John Wiley & Sons Ltd. 2004. Print. Fitzgerald, Robert. Foam Extinguishing System and Foam Concentrates. Pulawska: Tyco International Ltd. Hong Kong Labor Dept. Code of Practice for Metal Scaffolding Safety. (1st ed). Occupational Safety and Health Branch Labour Department.2001. Print. International Labor Office. Safety and Health in Opencast Mines: an ILO Code of Practice. Geneva: International Labour Organisation. 1991. Print. Kidde Fire Fighting. A Firefighter’s Guide to Foam. Exton: National Foam Inc. 2003. Print. Labor Department. Code of Practice for Safety at Work: lift and Escalator. (1st ed). Hong Kong: Labour Department. 1997. Print. Lafayette, Louisiana. Workshop on Crane Safety. Texas: Texas A & M University Press. 2000. Print. Sergeant, Chase. Confined Space Rescue. New Jersey: Penn Well Corporation. 2000. Print. Read More