What properties need to comply with Local Law 157?

As defined by the Housing Maintenance Code, the properties that must comply with Local Law 157 include private and Class A and B multiple dwellings.

• Private dwellings, generally including one- and two-family homes.

• Class A multiple dwellings, generally including apartment buildings occupied as permanent residences.

• Class B multiple dwellings, including transient residential buildings such as hotels, lodging houses and dormitories.

The specific requirements depend on the building classification, location of gas appliances and building configuration.

Where are natural gas alarms required?

Where a dwelling contains a permanent gas-burning appliance, an approved natural gas alarm must generally be installed in the same room as the appliance.

The alarm must be located at least three feet but not more than ten feet horizontally from the appliance. It must also be installed in accordance with the manufacturer’s instructions and applicable NYC requirements.

Additional requirements may apply when dwelling units are located above areas containing gas piping or gas appliances.

What type of gas detectors comply with Local Law 157?

Standalone natural gas alarms must be listed and labeled to UL 1484 and approved for their intended use. Depending on the building and device, approved alarms may be:

• Battery-powered

• Connected to a plug-in electrical receptacle

• Hardwired into the building’s electrical system

• Part of an approved monitored natural gas detection system

DOB does not endorse a particular manufacturer or model.

Who can install the alarms?

Hardwired natural gas alarms must be installed by a New York City Licensed Electrical Contractor who obtains any required permits.

Approved battery-powered and plug-in alarms may be installed by a building owner, maintenance worker or dwelling-unit occupant when permitted.

What are the requirements for hotels and other Class B multiple dwellings?

Class B multiple dwellings may install approved natural gas alarms in dwelling units or use a line-operated zoned natural gas detection system with central annunciation and central-office connection in public corridors and public spaces.

If a dwelling unit contains a gas appliance, an approved natural gas alarm is still required in that unit.

A line-operated zoned detection system requires the applicable design, plan review, installation, inspection and maintenance.

Who is responsible for maintaining the alarms?

The building owner is responsible for providing the required devices and replacing them when they reach the end of their useful life or become missing, damaged or inoperable.

Occupants are generally responsible for testing and maintaining battery-powered devices inside their dwelling units, including replacing batteries when necessary.

Owners should maintain records of installation dates, device locations and manufacturer expiration dates.

What should I do if I smell gas or suspect a leak?

Leave the affected area immediately. Do not operate lights, electrical switches, appliances or phones inside the building.

Once you are safely outside, call 911 and the gas utility. Do not re-enter the building until emergency personnel say it is safe.