My visit to USA in 1968 does not qualify me to opine on your building practices or Code. In Britain, our Building Regulations allow a householder to use a deadlock on outer doors - and this is officially encouraged. Could your Code be satisfied by placing a key in an adjacent keysafe?
If not, there are models suitable for fire exits. I was not intending to dilate on the various models in, for example, the Ingersoll and Bramah ranges - you can see the catalogues on the Internet. Suffice to say, both offer mortice locks with thumb turns on the inside, suitable for use where there is no breakable glass in or adjacent to the door. If there is, door security is inevitably at risk without a deadlock; is this what your Code requires? Breakable glass could be replaced by other forms of glazing?
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Ingersoll rim automatic deadlatch has a trigger action which throws the square saw-resistant deadbolt (without use of the key) when the door closes. There is an inside handle; this can be deadlocked from the outside by an extra turn of the key, a function which can be used when the house is unoccupied. There is also a fire exit version of this lock whose inside handle cannot be deadlocked.
The Bramah mortice deadlocks can be remotely operated with electric releases (not many electric releases are available for mortice deadlock bolts), and the locks can be contacted. These features allow them to be incorporated into both fire and burglar alarms. And just look at the size of those stainless steel deadbolts - using a hacksaw is slow work ... . For most of the last half century, Bramah keys as standard were ringbow: see the bottom key here:
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resembles the common cheap zinc diecast keys used in Britain for cheap wardrobe locks - but Bramah keys are welded stainless steel! In the last couple of years, however, the previously optional coin bow has become standard. It is a little larger diameter, and easier to turn.
Bramah and Ingersoll Impregnable locks are not cheap: they are high security locks, and I venture to suggest they offer better security than many locks more readily available to US customers. British householders also increasingly use window locks. In Britain, more burglars enter through insecure windows. Entry through back doors is more common than through front doors. Window locks which lock automatically when the window is closed, and only need the key to open are most convenient. There are makes and models for most types of wood and metal windows, e.g.:
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are numerous British locksmiths on the Internet who could supply customers by mail. I know most people begrudge spending money on locks - only strange people like lock collectors
*enjoy* buying locks. Nevertheless,
"The dread and anxiety, which every inhabitant of the metropolis and its environs must feel in the reflection that he sleeps with no other assurance of safety, but the hope that chance ... might direct the invaders of the night to some other victim, is an evil that cannot be contemplated without horror. To secrete objects of temptation, and to prevent access to them by every possible security, seems therefore to promise more towards lessening the number of robberies, which bring daily disgrace on the police, and disturb the peace of the cities of London and Westminster, than the dread of any punishment, which the law of England can inflict."
whilst expressed in old-fashioned language, is advice as true today as when Joseph Bramah wrote it in London in 1784! (This seems to be almost the earliest published crime prevention advice, although Jesus (first century AD) did observe that "If the householder had known when the burglar was coming, he would not have allowed his house to be burgled!" Be sober and vigilant, therefore. And if you cannot be at home and on guard all the time, prudence suggests good locks be fitted and used, until all men obey the commandments not to covet and not to steal.
There are cheaper British lever locks, conforming to "BS3621 Thief-resistant locks for hinged doors", e.g.:
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deadbolts, operated inside by removable key (or thumbturn) are also useful on doors other than final exit doors; there are many makers:
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Just out of interest, US readers might like to look at the British locksmiths' view of domestic security, used in the 'Sold Secure' scheme, intended for new homes.
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