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To; whom it may concern

dear xx,in relation to our discussion regarding Serviced Apartments ( i.e Class 3 'hotel' occupancy[where the short term occupant is not familiar with the building] ) in a building designed for Class2 ( Residential Dwelling ) occupancy, we can summarise our general requirements for insurancepurposes as follows;

1. From a lifesafety perspective, fire detection system alarms for Hotel rooms are required to beAS1670 systems which are monitored by the fire brigade ( considered a higher standard of firealarm response ) whilst, in many circumstances, residential dwellings may be permitted to havelocal alarms in the apartments - which is a lower standard of fire alarm response.

2. our standards for fire sprinkler protection were developed for insurance purposes & as arefollows; ( but are similar to Australian Building codes & Australian Standard AS2118 )

Multi-unit dwellings (such as an apartment building ) are permitted to use Residentialsprinkler design - 4 sprinklers ( @ no less than 2 l/min/sq.m for approved sprinklers ). Sprinklersmay be spaced up to about 36 sq.m ( depending upon the sprinkler type & design pressure ).

Hotel/Serviced apartment occupancy similar to AS2118 Appendix A2 (l) requires LightHazard sprinkler design - i.e 6 @ 48 l/min = 288 l/min minimum. Normally sprinklers are spacedno more than 21sq.m.

Hotels over 4 storeys we prefer to see an enhanced design similar to the Draft update toAS2118 Appendix A3.1 (h) which requires Ordinary Hazard Grp1 sprinkler design - i.e 5mm/min over 72 sq.m = 360. l/min minimum. Normally sprinklers are spaced no more than 12.3sq.m.

Note; The more closely spaced the sprinklers, the higher the water density they are able toachieve for the same pressure ( i.e a more capable system ).

This aligns reasonably well with United States NFPA standards which is acknowledged in thePreface to AS2118 as the reference for 'special' residential sprinkler design & is also ourprimary reference. NFPA has varying requirements ranging from;

2 sprinkler designs ( NFPA 13D ) for single unit dwellings

4 sprinkler design for residences below 4 storeys ( NFPA 13R )

6 sprinkler design for the residential portions of Hotel style occupancies ( which is a moreonerous requirement ) & a minimum of 4 mm/min for NFPA13 designs ( typically over 4 storeys).

There is also a notable difference in the sprinkler heads recommended.

Sprinklers in apartment rooms are typically quick response type Residential sprinklers with asmall orifice ( less than 10-12mm ) & K factor of as low as 4.32 metric. Sprinklers in Light hazard occupancies are typically sprinklers with an orifice around 10 -12mm & K factor around 8 metric. Sprinklers in Ordinary hazard occupancies are typically sprinklers with an orifice around12mm & K factor around 11 metric.

Each of the different sprinkler types requires a different end head pressure to achieve theiroptimum design spray coverage.

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In brief, it makes sense that the requirements increase as the risk increases. This is why we areconcerned when the occupancy class changes without a commensurate increase in the fireprotection design. Of course, if the building was initially designed as a class 3 building withproper sprinkler densities & proper monitored fire alarms we would have no insurance concerns.

A Class 2 occupancy in a Class 3 building is not a concern from a fire safety standpoint, asClass 3 standards may be regarded as a higher standard. But vice versa does not apply.

I hope this explains the basic differences in fire protection design.