Maryland Adopts Workplace Heat Exposure Standard
Maryland Adopts Workplace Heat Exposure Standard
By Melissa Menkel McGuire
In recent years, including the summer of 2024, Maryland experienced record-setting heat.
Rising and sustained heat increases the vulnerability of workers to heat-related illnesses and
injury. The recent heat-related death of a local public works employee underscores the dangers
of workplace heat exposure. In response to growing concerns about heat-related workplace
illness, on September 30, 2024, the Maryland Department of Labor issued Final Maryland Heat
Stress Standards (the “Heat Standard”). Available here.
The Heat Standard applies to employers with employees whose indoor or outdoor
employment activities expose them to a heat index at 80 degrees Fahrenheit or greater.
Exceptions include emergency or essential services that protect life or property, incidental
exposures of 15 minutes or less and work in buildings, structures or vehicles with a mechanical
ventilation system or fan that maintains the heat index at below 80 degrees.
Covered Employer Obligations
Covered employers are required to monitor the heat index in work areas throughout
shifts. Monitoring must be performed through either direct measurement of heat and humidity,
reliance on the local weather data reported by the National Weather Service or other recognized
source, or by use of the National Institute for Occupational Safety and Health’s (“NIOSH”) Heat
Safety Tool application.
Additionally, and as further addressed below, covered employers must develop a written
heat-related illness prevention and management plan, provide for an acclimatization period of
up to 14 days for heat exposed employees, provide shade access, and accessible drinking
water, implement high-heat procedures for when work areas reach or exceed 90 degrees
Fahrenheit, and implement an emergency response plan and provide heat stress training for
supervisors and employees
Requirements of the Heat-Related Illness Prevention and Management Plan
The written heat-related illness prevention and management plan must be available and
accessible to employees and, upon request, the Maryland Occupational Safety and Health
Program (“MOSH”). It must include plans for: 1) providing sufficient amounts of drinking water;
2) providing sufficient opportunities and encouragement to drink water; 3) recognizing the
symptoms of heat-related illness; 4) responding to suspected heat-related illness; 5) providing
employees with sufficient time and space to rest in shaded or cool, climate-controlled areas to
cool down; 6) implementation of rest break schedules as necessary; 7) considering
environmental conditions, workload, required clothing, personal protective equipment, and
alternative cooling and control measures when determining rest break schedules; 8)
encouraging employees to take rest breaks to prevent heat-related illness; 9) training
employees on the hazards of heat exposure and necessary steps to prevent heat-related
illness; 10) using and maintaining alternative cooling and control measures to manage heat; 11)
heat acclimatization procedures; 12) high-heat procedures; and13) emergency response.
High Heat Procedures
Employers must develop a written procedure, in a language and manner that employees
can understand, to address conditions when the heat index reaches 90 degrees Fahrenheit or
greater. The procedure must include a work and rest schedule that is adjusted for environmental
conditions, workload, and the impact of clothing and personal protective equipment. Unless the
Employer can demonstrate effective heat management through alternative cooling and control
measures, it must include work and rest periods for heat either in accordance with NIOSH
recommendations or provide a minimum rest period of 10 minutes for every two hours when the
heat index is between 90 and 100 degrees and a minimum of 15 minutes per hour worked when
the heat index reaches 100 degrees.
Rest periods must be provided in the shade and may coincide with scheduled rest or
meal breaks, but cannot be discouraged.
Alternative cooling and rest measures must be readily available and accessible to
employees at all times, they must be documented in writing and may not supersede other
requirements of the Maryland Standard.
During periods of high heat, employers must monitor exposed employees by phone or
radio, a buddy system or “other effective means of observation.”
Shade Access, Drinking Water and Emergency Response
Covered employers must provide a shaded area as close to the work area as
practicable. The shaded areas should be outside, open and exposed to air on three sides,
prevent a heat source from reducing effectiveness, be of a sufficient size for the number of
employees and configured to permit them to sit. Accommodation also must be made for removal
and storage of personal protective equipment. If providing an outdoor shade area is
demonstrably infeasible or unsafe, an employer may provide alternative measures that are
equivalent to shade. An employer also may provide an indoor area cooled by a mechanical
ventilation system as long as it meets the size and other requirements for outdoor shade.
Employers must provide at least 32 ounces of free drinking water per hour to exposed
employees as close to the work area as practicable. The water should be available at all times
while the work is being performed.
The emergency response plan must provide for an effective and accessible means of
communication at the worksite at all times as well as procedures for responding to signs and
symptoms of heat-related illness, contacting emergency services and transporting employees to
an area accessible to emergency services.
Acclimatization
Newly hired or employees who have been absent seven or more days must be
acclimatized to heat for up to fourteen days. Covered employers also must maintain a written
acclimatization schedule. That acclimatization schedule should include one of the following: 1)
a schedule with a gradual exposure increase of not more than twenty percent each time over a
period of five to fourteen days; 2) compliance with NIOSH’s recommendations for
acclimatization; or 3) a combination of gradual introduction and alternative cooling and control
measures.
Training
The Maryland Standard requires employee and supervisor heat training prior to
exposure to heat, annually prior to exposure and immediately following any suspected
workplace illness or injury related to heat.
Training must include information on the work, environmental and personal conditions
that affect heat related illness. It also must address the importance of acclimatization, water
consumption and rest breaks, acclimatization methods, types and signs of heat-related illness,
appropriate first aid and emergency response measures, and the employer’s procedures for
reporting signs and symptoms of heat-related illness and otherwise complying with the Maryland
Standard.
Training must be provided in a language and method understandable to employees and
include the dates of sessions, names of trainees as well as a summary of the training provided.
Documentation must be maintained for one year and made available to MOSH upon request.
