THERE have been at least three instances reported in newspapers recently of people being killed when boilers exploded, highlighting just how dangerous boilers can be and the importance of adhering to safety regulations concerning their manufacture, installation, use and inspection.
National Social Security Authority
Last week, three people died and four were injured when a boiler they were using to steam their tobacco exploded in Hwedza. High pressure caused the boiler to explode.
The previous week, a Banket farm worker died when a makeshift boiler he was using to cure tobacco exploded.
Earlier in the week in Bulawayo a 24-year-old Nkulumane man was killed when a boiler he was working on at a factory called Driveshaft Centre exploded, ripping open his stomach. The force of the explosion was such that the boiler shot through the roof and landed on the roof of OK Mart, some 160 metres away.
Steam boilers are dangerous. They are packed with energy. They can explode with devastating force if not manufactured, installed and used with care and if not well maintained and periodically inspected by professional inspectors.
That is why there are regulations, the Factories and Works (Boiler) Regulations, RGN 279 of 1976, dealing with the manufacture, installation, use, maintenance and inspection of boilers.
That is why it is important to adhere to those safety regulations. It is why requirements for inspections should be seen as potentially life saving and not be regarded as an inconvenience. It is not worth taking shortcuts or using improvised boilers. People’s lives may be at stake.
Steam boilers play an important role, not only in agriculture and forestry, but in many industrial sectors, including the textile, sugar, tea and paper manufacturing sectors and in hospitals, prisons, hotels and power generation.
The steam energy produced is used for energising materials and machinery and for processing needs.
The regulations specify that equipment must be manufactured to a standard approved by the Chief Inspector of factories and Works under the supervision of an approved Independent Inspection Authority and that it should not be used without a valid certificate issued by Nssa upon satisfactorycommissioning under the supervision of a Nssa Inspector of factories and works.
Many users, especially in farming areas, are ignoring these requirements. They are taking risks with people’s lives.
Complying with the regulations is a legally binding obligation. However, there is a moral issue involved as well, since failure to comply with them is putting members of the family, employees and property at risk. Dangerous boilers can easily cause accidents, fatal accidents where people lose their lives as a result of using dangerous boilers.
Even where rigorous safety requirements have been observed in their manufacture and operation, boiler parts do wear out, creating structural weaknesses.
Boilers are subjectto corrosion, vibration, stress, pressure, fatigue, temperature differences, pulsation and erosion. These can eventually create dangerous conditions which require a trained inspector to detect them.
Boilers should be inspected regularly to maintain a safe work environment, control unsafe acts and conditions and ensure operational efficiencies.Inspections should be carried out by operators and at appointed times by qualified Nssa Factory and Works inspectors.
Inspection activities that operators can undertake include routine heat surveillance, draft or excess oxygen adjustment and assessing heat balance in the boiler.
The tasks they are required to undertake are normally itemised in unit operation manuals and itemised checklists, or programmed in portable “intelligent” devices. The significant results of these monitoring activities should be recorded in a unit log book.
It is dangerous to ignore the advice of a Nssa Factory and Works Inspector. A hazard that goes unnoticedor is discovered but not rectified can result in powerful explosions, such as those that occurred recently, taking lives and causing considerable damage not only to the boiler but to other property as well.
There are makeshift boilers being used on some farms which do not comply with any standard. They are hazards in themselves.
Corrosion or erosions caused by poor quality fuel, weather and feed water may cause thinning of the boiler shell. If this goes unnoticed, severe thinning may occur and lead to an explosion.
Excessive pressure, caused either by the absence orfailure of safety measures or insufficient release of contents through safety valves, can cause such a high build-up of pressure that an explosion may occur.
Other problems include a low water level, caused through incorrect operation, faulty feed pumps or leakage resulting in the burning of boiler tubes, bursting of the boiler shell in fire tube boilers or permanent deformation of the steel drum in water tube boilers.
There are three main causes of boiler loss or damage. These are human failure, product faults and operational errors.
Human failure includes faulty handling, negligence or wilful acts, which may include the operation of boilers without certificates.
To reduce the likelihood of loss due to human failure, it is necessary to select suitably trained people for the operation, maintenance and servicing of boilers. It is also necessary to install on the boiler easily noticeable fittings and control elements, warning devices and recovery mechanisms.
Manning levels should be adequate. Only government-approved persons should be allowed to service boilers. That is a legal requirement.
Operational faults include inadequate maintenance, overheating due to scaling and failure to measure and regulate the pressure. To guard against loss due to operational faults, regular servicing, maintenance and overhauling is important. There is need for constant control and inspection of measuring devices.
Product faults include faulty material, faulty design or construction and faults in workmanship or installation. To prevent loss due to product faults, there is need for purposeful inspections by Nssa Factory and Works Inspectors at appropriate times. Components that have led to damage to boilers as a result of deficiencies should be replaced when it is noticed that they are deteriorating.
To prevent catastrophes due to boilers exploding, it is important that all boilers are registered with and inspected by the Factories Inspectorate to ensure compliance with the safety regulations governing them and their use.Failure of legally registered and professionally operated boilers is rare in Zimbabwe.
Talking Social Security is published weekly by the National Social Security Authority as a public service.
There is also a weekly radio programme on social security, PaMhepo neNSSA/Emoyeni le NSSA, at 6.50pm every Thursday on Radio Zimbabwe and Friday on National FM. There is another social security programme on Star FM on Wednesdays at 5.30pm.
Readers can email issues they would like dealt with in this column to email@example.com or text them to 0772 307913. Those with individual queries should contact their local NSSA office or telephone NSSA on (04) 706523/5, 706545/9, or 799030/1.