HC Deb 07 May 1982 vol 23 cc441-8

Motion made, and Question proposed, That this House do now adjourn.—[Mr. David Hunt.]

2.33 pm
Mr. Neil Thorne (Ilford, South)

It gives me great pleasure to see the Under-Secretary of State for the Environment, my hon. Friend the Member for Ealing, Acton (Sir G. Young), in his place to answer this Adjournment debate. I know how hard my hon. Friend tries to help hon. Members with their constituents' problems.

My hon. Friend will know that the majority of low-rise building before 1940 was in 9 in. brickwork and that since 1945 it has been mainly of cavity construction. By using the same volume of material and by creating a gap of about 2 in. between the two skins, and using only the same amount of total material, usually with bricks on the outside and an inner skin of thermal blocks, it has been found possible to reduce the heat loss through the walls by about half. In technical terms that means a U value reduction from 2.3 to about 1.2. I apologise for those technical details, but as a chartered surveyor I believe that this is a matter of considerable importance.

About 20 years ago it was realised that by putting insulating material into the gap, the loss could be reduced by more than half again so that one finishes up with a heat loss of about one fifth of the total heat loss that would have taken place through a 9 in. brick wall. Because of the enormous increase in fuel prices during this period there have been major advances in cavity wall insulation. This normally takes three main forms. It can be of mineral wool, urea formaldehyde foam or polystyrene granules. The mineral wool and polystyrene granules are manufactured off site and are back-filled into the cavity through the gaps after bricks have been removed or holes have been made to facilitate that operation.

On the other hand, urea formaldehyde, which is created by the introduction of resin and a hardening material, is pumped into the cavity where it hardens off, and during that process it gives off a vapour. Urea formaldehyde has been used for a long time, particularly in the medical world. It is, I understand, even used in small quantities in the making of bread. Therefore, the substance has been in common use for a considerable time.

Since a vapour is given off the operatives who work on site must use masks to ensure that they do not take too much into their lungs or eyes. However, if people are subject to the vapour and they are not properly protected they often complain of nausea, sore eyes, skin rash, headaches, general lethargy, muscular pain, insatiable thirst and disturbed sleep, and I imagine that there are probably other symptons.

In most domestic properties the inner skin of the cavity is load-bearing and therefore this is relatively continuous and impervious to the vapour. I am told that over 1 million domestic properties have been treated in this way. However, in a number of cases that have recently come to my notice, including an old people's home in my constituency, it appears that no adequate check was made before application to ensure that the inner skin was impervious.

A number of heating ducts, for example, breached the cavity. The architect who designed the building did not of course, have it in mind that the cavity would be filled with a substance that gave off vapour. As a consequence vapour was discharged into the premises while they were still occupied by residents and staff in March of last year. It was obvious that something had to be done, and in its usual efficient way, the local borough council, which has an excellent record for taking care of elderly people in the borough and which has extremely good relations with its staff, determined to do something as soon as possible. It called in the contractors and it was agreed that work should be done effectively to seal the inner skin. Therefore, the staff and patients were moved out about five weeks after the cavity had first been filled.

About five weeks later the patients and staff were allowed to return, the main remedial work having been carried out and the discharge of vapour having dropped considerably from the levels recorded when the substance was originally inserted. However, although the figures have continually dropped, during wet and windy weather the readings are inclined to rise giving positive signs in some rooms that the vapour is still present. The contractor left measuring apparatus on the site so measurements can be taken whenever necessary. Even on bad days the discharge is still within the limit that the factories inspectorate considers tolerable, but, nevertheless, it causes considerable distress, especially to people who were present when the work was originally carried out and who have now become especially sensitive to the vapour.

Recently, the problem has arisen at Hemel Hempstead, and in the constituency of my hon. Friend the Member for Southend, East (Mr. Taylor), who, unfortunately, is incapacitated and cannot be present, where a school has suffered. In all of these cases the problem appears to occur in unusual constructions. A house built conventionally with two skins usually has no difficulty, but in a purpose-designed building, such as a hospital, old people's home or school, often the architect had no knowledge or expectation that the cavity will be subsequently filled, so it was not designed to accommodate any such substance. Consideration should therefore be given to what might be done about the British Standards for dealing with the material.

Where it is desired to carry out such work, an inspection should be made of the site and an expert from the firm concerned should examine the structure, preferably using construction plans. Most properties which are likely to be treated will have been constructed since 1945 and it should not therefore be too difficult, through either the owner or the local authority, to gain access to plans for investigation to establish whether difficulties are likely to arise by the addition of a substance giving off vapour. Where plans are not available, the contractor should be required to carry out a pressure or smoke test to ensure that no inside emission is possible.

For example, in the structure in Southend the cavities around the windows and at roof level especially were open and the fumes free to escape into the atmosphere inside the building. That is, in my view, a failure on the part of the contractors, probably through ignorance. They did not check that that would be likely to happen, and I understand that the school has now been made unusable for a number of weeks. If that is likely, those people who are not wearing protective masks and clothing are bound to suffer.

We then come to the most important aspect of the case. Is that suffering likely to be temporary or is it likely to be long-term? If the latter, are we thinking in terms of five or 10 years, or could people be sensitised for the whole of their lives? Obviously, it will seriously impair their pleasure and their opportunity to find employment, because they will have to avoid any environment that might include this substance.

I understand that the Consumer Product Safety Commission in America has expressed grave concern over the use of the product and has instituted a ban on the use of urea formaldehyde, which is subject to ratification by both Congress and Senate. I should like to know whether the Minister has any information, either from the United States of America or as a result of research carried out recently in Britain, on the effects on health of foam vapour.

I refer particularly here to the answer that my hon. Friend the Minister for Housing and Construction gave in a written answer on 18 March this year, at c. 193. I am most anxious to know whether any known antidote has been established, and whether there are likely to be any long-term or more serious effects that my constituents could suffer through having been subjected to an excessive dose of this vapour when it was first used on their premises.

2.47 pm
The Under-Secretary of State for the Environment (Sir George Young)

I am very grateful to my hon. Friend the Member for Ilford, South (Mr. Thorne) for raising this subject today, because it gives me the opportunity to review the uses of the material, the problems to which it can give rise and the actions that the Government are taking to deal with it.

I would not dissent from the perceptive historical analysis with which my hon. Friend introduced his remarks. He gave the history of how dwellings in Britain have been constructed. As he said, urea formaldehyde foam has been used here for about 20 years to insulate the cavity walls of houses. It is an effective and relatively inexpensive insulant, and it has brought substantial benefits in energy conservation.

A broad estimate, which my hon. Friend mentioned—based on the figures of Audits of Great Britain Limited—suggests that about 1 million dwellings in Great Britain have been insulated with the material concerned.

The overwhelming majority of those dwellings have walls of traditional double masonry construction, by which I mean walls with brick or block outer and inner leaves spaced apart by some 50 millimetres. I appreciate, of course, that timber frame housing is now being constructed in increasing quantity in the United Kingdom, but this particular type of house still forms only a small fraction of the total stock, and information available to the Building Research Establishment suggests that very few houses of this kind have been insulated with urea formaldehyde foam.

In saying this, I would not deny the fact that UF foam has been used to insulate some houses not of masonry construction. It is not suitable where the inner walls are lightly built, in some cases consisting only of plasterboard which does not provide a sufficient barrier to formaldehyde vapour penetration.

I am also aware that UF foam has been used in hospitals, schools and non-housing situations, and that a particular type of foam has been used on a small scale to insulate lofts. The extent of those uses is currently being determined by the Building Research Establishment and I shall return to the Government's attitude to those uses in a moment.

Using ingredients of the right composition, mixed in correct proportions, and installed by trained operators in walls that are soundly built and of appropriate construction, UF foam does not give rise to significant problems of formaldehyde smell. The British Standards Institution reports that in a sample of over 150,000 houses insulated with this material under its certification scheme, there was a complaint of smell after eight weeks in only 0.04 per cent. of installations. The initial complaint rate was higher but in most cases the installer was able to take effective remedial action. Most of these were probably cases in which there were undetected defects in the inner masonry leaf, allowing easier penetration of the formaldehyde vapour into the dwelling.

Formaldehyde vapour, when it does enter the building, can sometimes cause irritation of the respiratory tract and the eyes of occupants. Formaldehyde is also known to produce sensitivity of the skin and respiratory tract in a small proportion of individuals.

We have no evidence that a significant proportion of people in this country are allergic to formaldehyde. If allergy is suspected, the normal allergy treatment is appropriate. If positive, the usual anti-allergy treatments are recommended. My hon. Friend referred to the reply given by my hon. Friend the Minister for Housing and Construction in a written answer of 18 March. This stated that the chief medical officer of the Department of Health and Social Security, who is the Government's senior adviser on health matters, has indicated that the completed studies of people exposed to formaldehyde vapour have not found any evidence that it causes cancer, changes in lung structure, or permanent impairment of lung function in man."—[Official Report, 18 March 1982; Vol. 20, c. 193.] Further research on animals in the United States is being evaluated by a DHSS expert advisory committee, and in this country and in North America several wide-ranging surveys of the health of people who have been exposed during their work to concentrations of formaldehyde substantially greater than will be encountered in insulated buildings are in progress.

Their results should be available next year. All the evidence on possible health effects of low-level and long-term exposure to formaldehyde is being reviewed by the expert committees who advise my right hon. Friend the Secrtary of State. I say this to emphasise to my hon. Friend that present evidence does not indicate any hazard to health at formaldehyde vapour concentrations liable to be attained in properly insulated dwellings. Concentration in such situations, where these have been measured, have in all cases been substantially below the limit value established to protect workers in industry.

Perhaps this is the point for me to remind the House that formaldehyde, as my hon. Friend mentioned, is not only used in UF foam. It is widely used in plastics, resins, chipboard, and many other products from which its vapour can also escape. It is an important biological preservative. In some industrial situations, it can attain much higher concentrations than in non-industrial buildings. Questions of its safety have much wider implications than those we are debating today. Because of the importance of this material, it is right that we give close attention to all the medical evidence as it comes to hand, and I can assure my hon. Friend that this is and will continue to be the Government's policy.

My hon. Friend mentioned the United States. It is perhaps right that I say something about the differences between the situation in North America and the United Kingdom. It is a fact that in both Canada and the United States concern over the emission and effects of formaldehyde vapour has led to a ban on UF foam in the former country and the proposal of one in the latter. But the circumstances are different. The majority of North American houses are of timber frame construction, with wide cavities and inner walls that are relatively readily penetrated by formaldehyde vapour. As I said earlier, we in Britain do not regard these as appropriate to insulation with UF foam, and have not normally used it in such dwellings.

Both Canada and the United States, moreover, have lacked the apparatus of control through building regulations, and of advice and guidance through the British Standards Institution and through a responsible trade association, which have been fortunate features of the British scene. I say this to stress that there are substantial differences between the United States and Canadian situations and our own.

None the less, I appreciate that the actions in North America, together with reports of cases in this country where formaldehyde has entered buildings and caused symptoms including irritation, have caused concern among architects and industry alike.

Very recently, the Royal Institute of British Architects has advised members who intend to use the foam to obtain warranties from the manufacturer, supplier and installer and to discuss use of the material with their clients in advance. It is clearly right that those in the building industry do all that they can to ensure that any installation is done using high quality ingredients, to a good standard of workmanship, and that purchasers understand what they are buying.

I must stress that we already have substantial control machinery. There are two British standards that bear on urea formaldehyde foam. The first, BS5617, specifies the quality that should be attained by the raw materials to be used, in producing the foam and the performance to be expected of the resulting foam if it is to be suitable for cavity wall insulation. A second British standard, which is in the form of a code of practice—BS5618—describes how the foam should be installed, and the properties of the masonry—masonry cavity wall that make it suitable for filling. The British standard lays great stress on climate, because our earlier concern with cavity insulation was that it would allow damp to penetrate through the outer walls of a house more readily.

The standard lays down conditions for exposure in terms of driving rain and also limits wall height. It also describes the essential procedures and precautions to be adopted by those installing foam. It does not deal with walls other than those of double masonry construction.

The British Standards Institution has also established a surveillance scheme under which firms conducting the installation of this material can be registered. Those thus registered are expected to comply with the two British standards and to undertake proper training of their staff. The Department of the Environment has issued type relaxation direction 4 under the building regulations, allowing firms registered with the British Standards Institution under this scheme to insert foam upon seven days' notice to a local authority. Those not thus registered would be required to make a specific application for each individual installation, and to go through the full procedures of local authority scrutiny.

In addition to those controls, the National Cavity Installers Association, as the relevant trade association, provides guidance to its members on the procedures for satisfactory installation of foam and on the training of personnel. I hope that my hon. Friend will appreciate that that adds up to a substantial framework of controls.

My hon. Friend mentioned two instances that he has brought to our attention. I take it that the Hyleford old people's home is the home to which he referred He has written to my Department and I shall shortly be replying, telling him that if the appropriate authority approaches the BRE for an investigation through its advisory service it would be happy to undertake such an investigation and to give advice on building and construction matters, on the usual terms of such investigations.

I take it that the school to which my hon. Friend referred was the one in Westcliff. My Department has not been involved in any investigation of the building, but we are in touch with the Health and Safety Executive and we are aware of the visits and measurements that it has made at the school and at the old people's home. I understand that the school is to be re-opened on 17 May, doubtless to the relief of the parents concerned.

My hon. Friend has made a number of points that deserve a response and I should like to stress that my Department is not content to rest at this point. My hon. Friend the Minister for Housing and Construction has instituted a substantial supplementary programme of research to ascertain more precisely the extent to which formaldehyde vapour does penetrate into the interior of buildings of various types insulated with UF foam, and the survey is looking at houses other than those of double masonry construction and installations in other types of buildings.

A review of the scope of building regulations in this area is also in hand, and we are in consultation with the British Standards Institution about the possibility of a revision of its standard, making it explicit that it is inappropriate to use this material in this form in any buildings other than those which combine double masonry construction with other features that make penetration of vapour into the interior unlikely.

Mr. Thorne

Can my hon. Friend help over the sensitivity that is acquired by those who are subjected to the vapour and whether they are likely to suffer for long? It appears that if a person suffers an excessive dose at some stage, subsequent minor doses can cause the original distress to return. Does my hon. Friend have any information on that and, if not, will he look into it?

Sir George Young

I am happy to give my hon. Friend such information as I have. Formaldehyde can cause irritation of the eyes and upper respiratory tract. The threshold for mild eye irritation may be as low as 0.01 parts per million in some particularly sensitive individuals; 4 parts per million and above causes the eyes to water in most individuals and higher levels will have marked irritant effects on the nose and throat. However, the available evidence from occupational studies suggests that those effects are reversible and that formaldehyde does not cause chronic impairment of lung function at the levels encountered in the work place.

As I said a few minutes ago, we have no evidence that a significant proportion of people in Britain are allergic to formaldehyde. If allergy is suspected, the normal treatment is appropriate and if positive, the usual anti-allergy treatments are recommended. If my hon. Friend wants any additional information, I shall be happy to give it to him in correspondence.

We are here dealing with a material that has brought substantial benefits to the community through energy conservation. We have not encountered the difficulties that have emerged in North America. We have hundreds of thousands of houses where the foam has been installed without any complaints arising; it has brought substantial savings to the occupants.

However, we are working on the strengthening of the framework of advice and control so as to guard against inappropriate use, and we are also keeping under close and searching review all the medical evidence about the toxicity of formaldehyde available both in this country and overseas as it becomes available to our expert advisers.

I hope that my hon. Friend will be satisfied that the Government are aware of the issues that he has raised and have formulated an appropriate response to them.

Question put and agreed to.

Adjourned accordingly at Three o'clock.