Site Hazard Assessment – An Essential Service - Updated April 2020

 

EBS Ltd has been successfully carrying out inspections of buildings and building sites, to protect operatives, visitors and occupants from exposing themselves or others to hidden hazards and potential dangers. 

 

For those contemplating renovation work on an old building, starting work on a new site or proposing an on-site inspection, this preliminary Site Hazard Assessment service could prove to be a vital first step.

 

The Site Hazard Assessment service can include any or all of the following, tailored to your particular project:

• Testing for Anthrax in animal hair lath & plaster 
• Mould levels, including identification for pathogenic & toxic moulds
• Lead & Arsenic levels in paint work
• Hazardous dust assessment & fibrous materials (other than asbestos) 
• Electrical components for possible PCB or mercury presence – visual assessment
• Timber treatment chemical assessment

 

Anthrax

Historically animal hair (that may contain Anthrax) has been used regularly in construction, usually as an addition in the mixture of plaster but occasionally it was used on ceilings to improve insulation.  It poses a serious hazard to anyone exposing it, even after many years of lying dormant within the fabric of the building.

Bacillus anthracis is in Hazard Group 3. It is a biological agent that can cause severe human disease.  It may also present a risk of spreading to the community but if properly uncovered and identified there is usually an effective prophylaxis or treatment available.

 

 

 

 

Restoration and Refurbishment of Historic Buildings

Although regulations to combat Anthrax were introduced in 1907, they were virtually ineffectual until the outbreak of the Second World War.  Thus, architects or those involved in refurbishment of historic buildings should be aware that sampling and analysis would be prudent in buildings over 50 years old to establish whether there is a problem.

 

The Control of Anthrax

• Removal of the infected material, similar to asbestos procedures.
• Disposal by incineration.  The standard followed should be the same as for clinical waste.
• Following incineration the residue may be disposed to landfill.
• Seek expert advice and briefing as follows:
• Briefing to the contractor and all involved on site should cover risk to health, HSE involvement, reservoirs, incidence, transmission, occupations, activities, personal hygiene, MS(B)3 carry card on anthrax, cautionary notice, clinical diagnosis, immunisation, legislation, safety procedures, signing permit to work, records, sampling methodology and emergency procedures.

 

Mould

Airborne moulds are ubiquitous and have evolved to exploit the man-made spatial ecosystems of our built environment, where they manipulate the microclimates and ecological niches of our buildings and feed on a variety of substrates. The problems of occupational exposure to moulds are not new but are gaining new prominence for the following reasons:

• Toxic mould and its health implications and legal cases throughout Europe and USA

• Demands for better standards of living to improve the health, comfort and productivity of the occupants.

• Increase in the incidence of allergic reactions in susceptible individuals.

• Energy conservation measures leading to sealed buildings.

• Climate change and flooding

 

In the last century the management of mould problems in buildings has largely relied on misunderstanding and misdiagnosis of the biology, ecology and physiology of the causal organisms.  Exposure to moulds and indoor allergens is a risk factor for the development of allergic reactions and the incidences of these problems are increasing at an alarming rate.

 

Most common micro-organisms in indoor air are as follows; Cladosporium spp., Penicillium spp., Aspergillus spp., Yeasts, Eurotium herbariorum, Wallemia spp.  Other micro-organisms include Bacteria, Viruses, Actinomycetes and Pollens.

 

Most common moulds from dust indoors are as follows; Alternaria alternata, Aspergillus versicolor, Aureobasidium pullulans, Mucor spp., Phoma spp., Yeasts Actinomycetes including Bacteria, and House Dust Mite.

 

Allergy problems in buildings reflect in the health, comfort and productivity of the occupants, often increasing the rate of sickness in the work place.  

 

The fundamental understanding and close dialogue between employees and human resources; facilities managers, health & safety officers; architects, engineers and building health specialists is essential in order to identify, evaluate, monitor and remedy allergic reactions in buildings.  Allergic reactions in buildings is a complex issue and allergic signs and symptoms, types of allergies, indoor allergens and their management is a growing concern to employers and it requires a multidisciplinary, integrated approach.

 

Buildings that suffer from dampness (rising or penetrating dampness), moisture problems due to condensation, fire and flood damage can significantly higher the number of micro-organisms in the indoor environment.  This creates problems for allergic patients.  A prolonged residual moisture problem may also cause issues for non-allergic people, who may develop several of the mucosal and general symptoms.

 

Lead in Paint

Up until the mid-1960s, lead was widely used in household paint.  Lead is dangerous if breathed in, swallowed or absorbed and can be a serious health risk as it builds up in the body over time.  In extreme cases it can be fatal. 

 

The lead in old paint presents an increased risk to health when paintwork is flaking, knocked or chewed by children or pets and particularly dangerous when sanded or burnt off in preparation for repainting.

 

If you live in an older property or plan a renovation project, there is a real possibility that poisonous lead could be locked in and hidden within the older layers of thick paintwork.  

 

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Hazardous Dust Assessment & Fibrous Materials (other than asbestos) 

To the uninformed, dust and fibres can look harmless but these particles can be a serious health hazard if breathed in and absorbed into the body.  Given the right set of circumstances, certain types of dust can even explode, causing injuries and in some cases fatalities.

 

Airborne dust particles have been associated with occupational lung diseases such as Pneumoconioses and various other diseases including cancer, asthma, allergic alveolitis and irritation.  A range of other non-respiratory illnesses may occur at much lower levels of exposure.

 

EBS Ltd scientists are able to collect, analyse dust particles and advise on the safe removal and disposure.

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Electrical components for possible PCB or mercury presence – visual assessment

In the 1930s, PCB (Polychlorinated Biphenyl) started being used as a dielectric fluid by engineers in the manufacture of electrical products.  This new coolant (often known as ‘Askarel’) was widely used in manufacture but was eventually found to be environmentally hazardous and the chemicals were finally banned in the UK in 1977.

 

Today, there remain a large number of installations still containing PCBs and more importantly these are not always labelled as containing ‘Askarel’ because the product was sold under many different Trade names. 

 

PCB is non-biodegradeable. The fluid can be absorbed through the skin, causing a skin rash called ‘chloracne’ and can instigate liver damage.  

 

When PCBs are subjected to high temperatures, they give off highly toxic fumes, so if they have been involved in a fire for instance, the building will be highly contaminated.  Unless this contamination is dealt with properly, it will remain a long-term hazard to health for anyone working on the site and any occupants thereafter.

 

Equipment containing PCB include, electrical transformers, power factor capacitors, heat transfer equipment, pole-mounted transformers, process heating equipment, vacuum pumps, high temperature hydraulic systems, electrical resistors, bushings and other high voltage equipment, fluorescent light ballasts, hospital diagnostic equipment and wire/cable coatings and insulation.

 

Mercury Testing

Mercury may be found in light switches, old barometers, batteries and electronic appliances in the past and more recently in LCD screens and Fluorescent lights. Historically, Mercury has been very useful for measuring temperature and air pressure and therefore many old thermometers, barometers and clocks may contain Mercury.

 

The inhalation of mercury vapour can produce harmful effects on the nervous, digestive, and immune systems, lungs and kidneys, and may be fatal. The inorganic salts of mercury are corrosive to the skin, eyes and gastrointestinal tract, and may induce kidney toxicity if ingested and Erethism (also known aserethism mercurialis, “Mad Hatter” disease, or “Mad Hatter syndrome”)

 

Timber Treatment Chemicals Assessment

A representative number of structural timbers can be sampled and analysed for the possible presence of toxic substances. Typical substances that have been used in earlier times include heavy metals such as lead and arsenic and several organic compounds.

 

In the past timber preservatives containing Pentachlorophenol (LD50 = 27mg/kg body weight) Dieldrin (LD50 = 10mg/kg body weight) and Tributyltin oxide (LD50 = 200mg/kg body weight) were in common use (the LD50 is defined as the lethal dose to kill 50% of the test population).  Even low levels of these chemicals often had 'side effects' causing skin burns or induced violent sneezing because they irritated the nasal membranes.

 

The presence of toxic substances on structural timbers should be taken when formulating working practice methodology. An assessment for the presence of timber treatment chemicals should be carried out for a number of reasons.

 

Testing for the presence of these chemicals is recommended if existing timbers are to be cut or reused in a refurbishment.

 

If insect or fungal decay are found in timbers and a chemical treatment is proposed (by a company with a vested interest in selling chemicals), it is prudent to check whether the timbers have previously been treated.  This will prevent duplicating the treatment, cut costs, and reduce any possible health implications and environmental impact. It is important to note that EBS does not recommend the use of chemical treatments to combat fungal decay and controls fungal infestation (Dry rot and wet rot) by environmental means. 

 

Analysis results can confirm whether any timbers have significant levels of toxic metals such as lead and arsenic and for the presence of any toxic organic treatments.

 

Successful case studies include; Somerset House, British Museum, Belgrave Square, Kings College, University College London, Royal College of Ophthalmologists, Kings Cross Railway Station, Trinity College Dublin, The National Gallery, Tate Library, Rothschild Archives, Jersey, Guernsey and Sark Islands, English Heritage and The National Trust.

 

Copyright: Environmental Building Solutions Ltd April 2020