Last Updated on April 4, 2024 by Alarm New England

The Massachusetts Executive Office of Public Safety and Security recently stated that of all the fire-related fatalities that occurred in 2014, approximately 25 percent happened in homes without smoke alarms.

A startling 12 percent of the remaining fatalities occurred in homes equipped with smoke detectors that were not functional. These harrowing stats have led to the expansion and development of smoke detection laws and requirements in Massachusetts.

The Massachusetts smoke detector law now requires all homeowners to install up-to-date smoke and carbon monoxide detectors that will alert residents to the presence of smoke, fire, or deadly gases. The newest regulations give Massachusetts residents clear instructions on when and how smoke detectors need to be assessed, maintained, and replaced. Homes of any age generally require one smoke detector on every habitable level of the home, and a smoke detector on the ceiling above each stairway. There are different rules and regulations for homes built before January 1, 1975, between 1975 and August 27, 1997, after August 27, 1997, and after January 1, 2008. Therefore, it is important to know when your home was built so you can be prepared for your homes’ unique requirements during and inspection.

Placing smoke detectors in the correct areas can make them more effective and prevent fires from becoming deadly. By tightening up the law, the state hopes to prevent and reduce smoke and fire-related fatalities altogether.

active smoke detector massachusetts

Knowing the most recent Massachusetts smoke detector law and understanding its regulations is essential to keeping your family and home safe in a fire or gas leak. Here is what you need to know to stay up-to-date with the detection laws for smoke detectors Massachusetts.

Why Are Smoke Detectors Important?

In the United States, approximately 2,000 people lose their lives in residential fires every year. According to National Fire Protection Association, almost 50 percent of home fires happen while the residents are asleep.

Without early detection, smoke and deadly gases begin to spread quickly and move faster than heat. In these cases, victims are likely to die from smoke or gas inhalation—not from actual burns. This is why effective and early detection is of the utmost importance. The majority of fire-related fatalities occur because families were asleep and unaware of the danger.

That’s why smoke alarms are an absolute necessity. These systems alert families, giving them adequate time to escape without being harmed. Properly installed and well-maintained smoke and carbon monoxide detector systems are now required by MA smoke detector law to ensure residents take their safety seriously.

If you live in or near Boston, MA, CT or RI, we can help bring your current smoke detectors up to Massachusetts law code and provide professional smoke alarm monitoring. This means that we can immediately dispatch the fire department to your home if your smoke detectors go off without your knowledge. We take home security in Boston seriously, so you can rest assured you’re getting the best protection from up-to-date technology that’s UL approved and NFPA 72 compliant.

The Two Main Types of Smoke Detectors

Today, there are two main types of smoke detection devices: photoelectric detectors and ionization detectors. According to the NFPA, it’s best to use both ionization and photoelectric detectors in your home for optimal protection.

The photoelectric smoke detector is more reliable and efficient, but many older homes have ionization detectors. It’s important to know the differences between these two types of smoke detectors so you know what’s best (and legally required) for your home protection. If you’re not sure about which type you need, contact an alarm company near you and ask and they may be able to assist.

Photoelectric Smoke Detectors

As the more recent and advanced technology, photoelectric smoke detectors are becoming the popular choice for equipping your home with detector systems.

Photoelectric systems come with both a light source and a light sensor. Both are arranged so that the rays from the light source hit the light sensor, working in tandem. When a fire occurs, smoke particles cross the path of the light beam, leaving some of the light scattered, redirecting it to the sensor. This immediately activates the smoke detector, sounding an alarm to alert you and your family.

Experts state that this technology is undeniably the most efficient and effective on the market. Photoelectric smoke detectors have the ability to detect both smoldering (slow) fires, which are more likely to result in fatalities, as well as flaming (fast) fires.

Photoelectric detectors are also less sensitive to smoke from steam or cooking, reducing the likelihood of unnecessary false alarms.

Ionization Smoke Detectors

The slightly older technology of ionization systems has a small radioactive source used to charge the air inside the system. An air current crosses through the chamber, running between two electrodes to create a circuit. When smoke makes contact with the system, it blocks the air current, causing the alarm to trigger.

In comparison to photoelectric systems, ionization technology is able to detect flaming fires most efficiently and smoldering fires at a much slower rate. This may also lead to increasing false alarms as a result of cooking smoke or steam.

smoke alarm for home cooking

Change in Smoke Detection Laws in Massachusetts

In 2010, Massachusetts smoke detector laws shifted significantly. The previous smoke detector laws were only implemented when a transfer or sale of property took place. The new 2010 regulations were created to ensure that homes that didn’t change ownership didn’t fall through the cracks.

These laws are generally enforced when a property is being renovated or sold. Without a verified certificate of inspection, the house cannot be sold or legally change hands. But even if you’re not selling your house, you should update your smoke detection systems to meet the following requirements to ensure your home and family is safe.

Minimum Smoke Detector Requirements

The new regulation requires all owners of a residential building to install either photoelectric or combination detectors (which is both photoelectric and ionization). Additionally, any ionization detectors must be placed a minimum of 20 feet away from a kitchen or bathroom. Photoelectric systems, on the other hand, can be installed anywhere in your home.

Under the new law, all homeowners have to assess the fire prevention systems currently installed on their properties and have the option to install a combination system that possesses both photoelectric and ionization detectors or install two separate detectors.

These are the basic requirements homeowners must meet to receive a verified certificate of inspection from a local fire marshal:

1. All preventative fire systems are required to be photoelectric or combination

2. All systems must have sealed, non-replaceable 10-year batteries.

Recommended Requirements for Additional Protection

These are the optional recommendations for added protection.

1. Non-obligatory smoke systems are allowed to have replaceable batteries.

2. Non-obligatory smoke systems may be either photoelectric, ionization, or combination type.

Massachusetts Carbon Monoxide Detector Law

If you are considering selling your home in Massachusetts, you also need to ensure your home meets the state carbon monoxide detector law. This law is referred to as Nicole’s Law, named after 7-year-old Nicole Garofalo who died after a blocked heating vent resulted in carbon monoxide accumulating in her home.

The law states that when selling your home, it is mandatory to have a functional carbon monoxide detector installed.

Carbon monoxide detectors are a requirement for any home that has any of the following:

  • Boiler
  • Furnace
  • Water heater
  • Fireplace
  • Any other appliance, apparatus, or device

This regulation states that there must be a detector on each completed level of the home placed within 10 feet of each bedroom door. In this case, detectors need not be hardwired, and battery-powered or plug-in options are usually popular.

According to Massachusetts’s law, the following carbon monoxide detectors are permitted:

  • Plug-in with a battery backup
  • Battery powered
  • Hardwired
  • Low voltage
  • Wireless alarms
  • Combination smoke and carbon monoxide detectors

As per all smoke detector regulations, inspections can be done by MA local authorities, such as a fire marshal, who will then give you a verified certification upon successful completion. This certification is valid for two months, and you can’t sell your home without it.

It is thus imperative to understand how Massachusetts smoke and carbon monoxide laws work hand in hand. Without complying with both of these regulations, you will not be able to sell your home.

How to Prepare Your Home for a Smoke and CO Alarm Inspection

To ensure your home is ready for a smoke and carbon monoxide (CO) alarm inspection, start by locating all the smoke and CO alarms throughout your residence and keeping a record of their locations. Next, research when your home was built and check for any recent building permits, as this information will help you understand the specific alarm requirements for your property. Carefully inspect each alarm, noting its age, whether it’s functioning correctly, and if it has expired or needs replacement. Finally, test all the alarms in your home to verify they are operating as intended. By following these steps – finding and documenting all alarms, understanding your home’s requirements, checking alarm ages and functionality, and testing each unit – you can confidently prepare for a successful smoke and CO alarm inspection.

When Should You Replace Fire Alarms?

Many residential fires occur in homes that have detector systems installed. There are many reasons why these systems may fail to work, including batteries not being changed, system failure from exceeding its shelf life, or removal of the system altogether.

It is for that reason that older homes are expected to have 10-year battery lives on their detector systems. If you are unsure of the lifespan of your system or whether the system has exceeded it, you can always check the date at the back of the alarm system panel.

If there is no date stamped on it, chances are the system has already exceeded its life span and does not qualify, meaning you will need to replace it immediately.

Massachusetts Legal Requirements for Replacing Alarm Systems

According to the Board of Fire Prevention regulations, the state fire code now requires that homes have smoke detector systems that are not expired.

When replacing your smoke detector system, these are the minimum Massachusetts smoke alarm requirements that you must follow (on top of the conventional manufacturer’s instructions):

  • System must be photoelectric
  • System must have an easily accessible silence button
  • All alarms can either be solely photoelectric or combined with an ionization and carbon monoxide systems and technology. (It is important to be aware that carbon monoxide parts can fail well before 10 years and need to be checked regularly.)
  • Alarms must be on every liveable level of the residence (including basements or attics)
  • All additional battery-powered alarms that are older than 10 years must be replaced
  • All alarm replacements must have 10-year sealed, non-rechargeable, and non-replaceable battery packs
  • In homes that have two or more residents, detector systems should be installed in all common areas
prevent home fire incidents

Is Your Home Safe and Compliant With These Regulations?

These laws have been implemented in Massachusetts to avoid unnecessary fatalities that result from dysfunctional or badly installed smoke and carbon monoxide detector systems. All codes outline the compulsory minimum requirements for you and your family’s protection.

In many cases, simply following the minimum requirements is not enough—it’s safer to follow the recommended precautions as well. Going above and beyond the minimum requirements eliminates potential issues from causing harm to you or your family.

In some cases, you may want to find a private company to install and provide professional alarm monitoring services for your smoke alarms. Should a fire or carbon monoxide leak occur at any time, the system will notify the 24/7 monitoring center, who can then dispatch emergency services immediately if need be.

This keeps your home and family safer, especially if you’re asleep or away from your home. Contact Alarm New England today and we can help you update your smoke and CO alarms to meet current regulations and provide you and your family with the highest level of safety.


If you have questions about the most up-to-date local requirements for smoke alarms that we didn’t answer above, please contact the local fire marshal or the Massachusetts Department of Fire Services:

Stephen D. Coan, State Fire Marshal
P.O. Box 1025 State Road
Stow, MA 01775
Tel: (978) 567-3111

Timothee Rodrique, Director
Division of Fire Safety
Tel: 978-567-3301