Sunday, September 18, 2011

Karl Popper, Design, Regulations and the Fallacy of Evidence-of-Suitability

DanQuo's applied science: Encountering Popper: “We have to admit that, strictly speaking, scientific laws cannot be proved and are therefore not certain.”[1] I have just recently beco...

Karl Popper, remember reading about in New Scientist magazine in the 1980's, never read his books, but often refer to the classic example of the white and black swans, and the problems of collecting evidence. Whilst I otherwise refer to Edward de Bono's idea of proto-truth. The refinement of language can cause all sorts of problems in communication, the meanings of words is not always clear: most especially in engineering. Engineering involves transforming objects and creating new objects, and what names to give these derivatives and new creations? When is a table, not a table? When does an object belong to a particular class of objects and when does it not? Where are the boundaries and where are the overlaps, what is contained within what? Each new instance of an object within a class, is it a repetition of something which forms a subclass, or is the start of a new subclass?

Sometimes the role of designer seems to be more one of technical lawyer, than one of dealing with the physics or mechanics of a system. When is a wall a partition? When is a partition a barrier? When is a barrier a partition? When is a veneer not a veneer? What is cladding? What is a buildings fabric? What is fabric and when is fabric not a textile? When is the proof load in the code inappropriate for testing? Is a destructive testing requirement appropriate for testing existing construction? What is structural failure? What is fitness-for-function, or suitability-of-purpose?

If think have an answer for these questions chances are, someone else will have a different answer. Design and acceptability of the design is a matter of subjective judgment. In an attempt to minimize the variation in judgments we have regulations and codes of practice: but these are open to interpretation. The actual written word in the code versus the intent and meaning behind the code, magnified by the views of different people. To obtain approval from the authority having jurisdiction (AHJ) there is a requirement to present evidence-of-suitability. Thus a building is not considered compliant with the performance based requirements of the building code of Australia (BCA), unless adequate evidence-of-suitability is presented. Many people in the industry haven't quite got a grasp of this requirement: they think that all that is required is to provide a description of the proposal then approval will be granted.

There are two basic options, only one of which is desirable:

1) Supply evidence to a court after failure.
2) Supply evidence to an AHJ before implemented.

Supplying evidence to a court is not a good option. If something ends up in court, then already have some one who is piling up evidence that the product is defective and is not suitable for purpose: the prosecution. The defence, is thus going to have difficulty demonstrating fitness-for-function, when there is already a case of failure before them.

All products, once released to the environment, to the market, will be put to all manner of uses beyond the intents of the designer. So after failure, the issue is not so much as whether the product was fit-for-function, but rather was if suitable for the end-users purpose, and was there anything misleading which indicated that it was suitable. This all leads to more and more disclaimers on products, all explicitly expressing what the product is not suitable for, rather than indicating what it is suitable for. But often times these appear silly: for example hammer with notice not suitable for hardened nails. What is a hardened nail, how would you know if using one? If a carpenters claw hammer, then expect to use with nails driven into wood, rather than nails driven into masonry. But if driving nails into masonry then preferable that are wearing safety glasses in the first place. If nail ends up in hammer rather than wall, did the manufacturer really need to have listed all areas that it is not suitable for? Would a user, use a wooden mallet or rubber mallet to drive nails? If chips fly of the head of the hammer and damage someone's eyes, is it really the manufacturers responsibility. A lack of common sense and personal responsibility wastes a great deal of designers and manufacturers time in court.

The result is more an more legislation and regulation, with increased requirements to seek approval from an appointed authority having jurisdiction (AHJ) before implementing anything. The problem with regulation however is confusion over the purpose of the approval. For example I often get clients who are unhappy with local councils (AHJ) and some engineer. Especially builders, but occasionally owner-builders, the usual complaint is something is over-engineered and otherwise unbuildable, and everyone (council and engineer) are idiots, especially council for approving. The council however is not concerned with the buildability of a proposal, the councils concern is whether the proposal imposes inconvenience or hazard on the community. If the proposal does not pose an inconvenience or hazard, then can go ahead and build, if the building proponent did not figure out how to build it then that is their problem.

As for being over-engineered, that is a silly term. Something is either over-sized due to a lack of engineering, or under-sized due to a lack of engineering. The problem is only going to be resolved by providing more engineering. The issue to resolve is: to stop the builder leaving their drawings, requesting calcs-for-council and then clearing off. Got to get the builder to sit down and think about what they actually want to do, are willing to do, have the resources to do. This is planning and design, not the crunching off numbers. It is important, because if check the numbers then the first design is most likely to turn out compliant, and not over-engineered as they say. The problem is that whilst the structural numbers may be correct, it is not a design-solution to the real problem. As they say 2/3rds of the solution lies in putting the question correctly, running into a consultants and requesting calcs-for-council, was not putting the question correctly: they got what they asked for, but it is not what they needed.

Legislation and restriction of service doesn't help resolve this issue, it is those who are currently on the national registers who are largely responsible for just pushing out the numbers: simply meeting the requirements of legislation. At present the national professional engineers register (NPER) is a voluntary thing, and legislation varies between the states which makes reference to such register: some states have their own additional registration and/or licensing schemes. So whilst maybe on the national register, have additional fees to pay in each state. Any case South Australia, does not have any independent registration system, and the there is no restriction of trade: such likely to be opposed on basis of federal fair trading laws. Other states had their systems prior to federal laws, and on review were able to demonstrate retention of: not that the reviews were really open to the public. Those with the authority simply decided to retain such authority, with nonsense about public safety. In South Australia (SA) such policies are typically seen as a grab for work, and opposed. In SA the legislation only restricts with respect to the approval process, the authority having jurisdiction. So anyone can supply design services, if person chooses to employ a drafter instead of a designer, then the buyers problem, if the application for building approval keeps getting bounced back and forth whilst the drafter attempts to supply all the required description of proposal and the required evidence-of-suitability. Whilst all this regulatory compliance is taking place there is little consideration of buildability taking place.

I would like to say that the people should employ an architect or engineer in the first place to ensure design which complies and which is buildable: unfortunately it does not happen to be true. Why? Because all swans are not white. As the advertising goes: oils ain't oils. It is also difficult for the public to know what they need, at the same time for consultants to know what is required. So when people phone consultants up, asking for a fee, its like asking: how long is a piece of string? Consultants really need to see what is involved, for much of engineering, that typically involves drawings produced by others. For large building projects the initial drawings likely produced by architects, and the architect seeks the services of engineers for specialist input. For smaller projects, it is likely the owners or builders who approach the engineers directly. Unfortunately the assumption for the smaller projects is that the design is complete, and calculations are just required from the engineer, to demonstrate compliance of the proposal with the building code: that is the engineer provides evidence-of-suitability in the form of calculations. The assessment of suitability however only gives consideration to the minimum acceptable performance of the end-product in service and at extremes of operation.

The suitability for fabrication, handling and transportation and construction are seldom considered on the smaller projects: massive projects no choice in the matter: all the available equipment and resources of society are pushed to the limits. For structures, when the available steel sections are not large enough, then really have to consider fabrication, when larger than will fit on the back of truck, then transportation has to be considered. However, if a steel beam has to be spliced, that is not just a fabrication issue, it is also an end-product performance issue which requires approval by the AHJ.

If a characteristic is assessable against the building code of Australia (BCA), or other national standards then it has to be disclosed in the development approval or industrial plant licensing application. If it is not assessable then it doesn't need to be disclosed. See the problem: evidence-of-suitability only applies to that which is disclosed, to that which is assessable under the regulations: that which is beyond the scope of the code is ignored by the regulators and all those that supply services solely for gaining approval.

In particular there is much confusion about the requirements for seeking development approval. Development approval in South Australia comprises of two parts:

1) Development Plan consent
2) Building Rules consent

Not all projects require both consents. Internal modifications to a building, may only require building rules consent. There is also a matter of occupational, health safety and welfare (OHS&W) act and regulations. If a space is used as a work space, then it has to be compliant with the building code. When a building is new, then it will comply with the version of the BCA current at the time building permits were granted. The BCA is revised each and every year, to resolve ambiguities and otherwise in an attempt to remove state differences. A developer can get development approval for an empty warehouse (despite lean: there are lots of warehouses being built.). Once built, the tenants move in and fill with industrial racking, this racking can make the building cease to comply with the BCA, the racking gets in the way of access to required exits, increasing travel paths beyond those permitted. The building that was compliant based on submitted evidence-of-suitability is no longer so, and in all probability no approval was sought for the variations.

So another problem have to deal with, is observations of the built environment. Why can I not do that, for they have? Just because something is present in the built environment does not mean it was granted approval, and if it was granted approval it doesn't mean it will be granted approval today. When changes to planning and building rules change, the new rules are typically not imposed on existing. However if an accident occurs in a workplace, the workplace is likely to be assessed against current regulations, not those current at time of development approval. Failure to upgrade the workplace maybe seen as negligent: now compliance may be impractical, and therefore the intent of the code needs to be addressed and alternative solutions implemented, justified by appropriate documented evidence-of-suitability. The real issue is not about going through approval, but about having adequate evidence-of-suitability to defend decisions taken, should those decisions be placed under question. This is a particularly important for OHS&W for there is no formal regulated assessment process, except for a few items of mechanical plant (eg. pressure vessels, cranes). The OHS&W regulators are more likely to prosecute people for breach of relatively generic regulations after some one has been injured rather than go around attempting to impose: employers and employees are typically equally responsible for a safe work place. Collecting evidence-of-suitability after an accident has occurred is the wrong time to be doing so.

Suitability cannot however be based on mere compliance with codes of practice, or observations of what others are doing. For example one situation, all along one road transportation companies, with loose gravel driveways and parking spaces. Apparently the truckies prefer this, it makes it easier to turn, unfortunately it kicks up a lot of dust. The result of this dust is that new transportation businesses in the area cannot have loose gravel surfaces, the result is typical implication of concrete paving. The gravel is permeable and storm water can soak into the ground, typical concrete paving is impermeable and so expensive drainage systems need installing to limit surface run-off and limit drainage to street main to that before the development. This makes it more expensive for new businesses in the area.

The problem with prescriptive based regulations to an apparent problem is that it limits the scope of possible solutions: it hinders innovation. However performance based regulations are more complex to write since need to identify the desired characteristics with out reference to anything specific. Also often times in design required characteristics are often contradictory and conflicting. As far as I know the truck drivers requirements cannot be met by any material which will also meets the regulators requirements. On the other hand the problem seems more like an issue with the trucks: after all the roads and destinations are not surfaced with gravel. Tarmac, asphalt may provide the desired surface the truckies are looking for, but I believe such surfaces abandoned in ports and harbours due to the expense of maintenance. Gravel needs occasional regrading, the asphalt more difficult and expensive to fix.

Suitability has to do more than dig down to the required characteristics, do more than simply collect and compile evidence-of-suitability. The lack of suitability also needs to be addressed. The concrete pavement may be suitable relative to the regulations and public, but it is not suitable relative to the needs of the end-users the people mostly directly affected by the design.

Much of the work that flows through the office where I work, I classify as "nominally existing":

1) Illegal construction for which notice has been issued requiring application for development approval or removal of the construction.

2) Manufactured structural products for which require revised calculations to revised code of practice, or for custom features.

3) Applications in council (AHJ) and awaiting further information.

In all situations there is a lack of available evidence-of-suitability. It is difficult to assess things which cannot be seen. For example how long is the bolt, that disappears into the wall, what fasteners are used inside a wall, and what is buried in the ground? Then there are properties of materials: what strength grade timber as been used, what grade of bolts? For a period steel was relatively simple, it was Australian made by BHP, but no longer can have such certainty. Additionally the strength of steel has varied over the years, and always had different strength grades of hollow sections. So need some non-destructive means of assessing what has gone into a structure. After failure, easy to take test tokens of materials for testing, and dig things up, and get inside. Determining if something should be demolished is not so easy: councils don't want to look bad moving in a demolishing someone's building: engineers don't want to approve something that may be hazardous, on the other hand also don't want to waste materials or effort. Regulations can get in the way: just because something does not comply with codes does not make it a hazard to the community or to other future users. The intents of the codes have to be considered, and also the objects to which they apply.

Pedantic code pushers only approve subject to the exact wording of the codes, those that understand or otherwise contributed to the writing of the code are more likely to refer to the intent rather than the letter of the law. For example the proposed object does not have the characteristics of a swan, therefore does not have to comply with performance criteria for, on the other hand the intent of the code was not limited to swans, and therefore some performance criteria do apply, but the level of performance may be extreme for the object under consideration.

The fundamental requirement is to document the evidence-of-suitability, but also giving due consideration to situations for which is unsuitable, most especially those situations where suitability may be inferred or implied.

Not everything is regulated explicitly. The most fundamental laws are those for fair trading which require goods and services be fit for purpose. Those prosecuting a supplier have to demonstrate that the product supplied was not fit for the purpose that the supplier indicated that it was fit for. That is the end-user cannot simply demonstrate that the product was not fit for their purpose and failed. An end-user has a responsibility to select products suitable for their needs, if they cannot properly specify their needs then they will have difficulty selecting a suitable product. Thus some products require the end-user to appoint someone else to select a suitable product for their needs. But how to select a suitable person to select a suitable product for such needs? Professional qualifications represent a rapid filter for the selection process, but not a reliable filter and not a particularly helpful filter. The end-user still needs to dig below the surface, and get their own evidence-of-suitability as well as check out the lack of suitability.

Most businesses advertise on the basis of suitability, rather than disclose their unsuitability. To start with traditionally architects and engineers were not permitted to advertise: whilst this has been relaxed in recent times: there is a restriction on simply describing projects worked on: no grandiose claims permitted. No architects or engineers would say they are unsuited for monumental type projects, at the very minimum they at least want to be offered such projects. The description of past projects however represents evidence-of-suitability, finding out that a consultant was more of an hindrance on a project is more difficult for the public to find out, unless the project was in the mass media.

Perspective is important. Many consultants seem to think a good idea to promote they were involved with multi-million dollar projects. However from the perspective of others, the response may be, if more competent consultants employed the project would have been off far higher quality for significantly lower cost. More than one way to skin a cat, and more than one perspective on things. Collecting evidence of suitability is one perspective, collecting evidence of unsuitability is the complementary perspective.

Don't just rely on supporting evidence also seek out the contrary.