It's Shabbat morning, and Hartman, 51, her thick, dark tresses uncovered, is milling about at Shira Hadasha on the women's side of the mehitza, the barrier that separates the sexes in an Orthodox sanctuary.
Shira Hadasha's mehitza runs front-to-back so that both men and women can see the bima and have equal access to it.
For people who don't have nuclear families to sit with or who just lost a spouse, the mehitza helps them find a seat, a place where they belong.
Women's prayer groups helped provide the foundation for the three-decades-old and highly successful Women's Tefillah at Rabbi Avi Weiss' Hebrew Institute of Riverdale in New York, and Yedidya, a Jerusalem congregation founded in 1980 that runs a mehitza from front to back.
For those who are not Orthodox and might never have considered praying in or even visiting a shul with a mehitza, Shira Hadasha makes that world less daunting or strange.
Having largely followed Reform and Reconstructionism on women's issues, it must now carefully delineate for its members what still sets it apart from these movements; the mehitza
dividing Conservative from Orthodox Judaism, by contrast, is relatively well defined.