Towards the end of the Book of Numbers, we read about the cities of refuge. These were six cities in the Land of Israel where a person who killed someone out of negligence could find refuge from avenging relatives. If they found him outside of these cities, they could kill him.1 We see that the Torah considers the inadvertent murderer to be guilty to a certain degree.

This same theme – that a person is responsible for deaths caused by his negligence – is expressed in Deuteronomy2: "When you build a new house, you shall make a guardrail for your roof, so that you shall not cause blood [to be spilled] in your house, lest someone fall from there."

The guardrail must be sturdy and at least ten handbreadths highThe Torah also considers one responsible for safeguarding one's own health and wellbeing. As the verse states3: "But beware and watch yourself [lit. your soul] very well." In connection to this, we present a collection of laws pertaining to guarding the life and health of oneself and others:

Guardrails

  • It is a Torah obligation to build a guardrail around one's roof4 lest someone fall off the roof and get hurt or die.5 This guardrail is called a ma'akeh.
  • The guardrail must be sturdy and at least ten handbreadths, or approximately three feet, high.6
  • There is no requirement to build a guardrail on a roof that is not used by people.7
  • When erecting a ma'akeh, one should recite the following blessing: Ba-ruch a-tah ado-nai e-lo-hei-nu melech ha-olam, a-sher kid-e-sha-nu be-mitz-vo-tav vetzi-va-nu la-asot ma-akeh. ("Blessed are You, Lord our G‑d, King of the Universe, who has sanctified us with His commandments, and commanded us to construct a parapet.") One who is erecting the ma'akeh for someone else should conclude the blessing: al asiyat ma-akeh ("...commanded us concerning the construction of a parapet"). 8
  • Included in this Torah obligation is the obligation to build a proper, sturdy fence around a ditch that is on one's property, even if that ditch has water in it.9 This obviously includes a swimming pool. Alternately, one may cover the ditch or pool.10 However, one does not recite a blessing when covering a pool or erecting a fence around it.11

Other Precautions

  • A father is obligated to teach his children how to swim.12
  • One may not wade through rushing waters that are higher than one's waist.13
  • It is forbidden to drive a vehicle at a dangerous speed.14
  • One may not drink from a river without first drawing the water and inspecting it for leeches.15
  • One may not go on a dangerously unstable bridge or walk under a shaky ladder.16
  • One may not own a dangerous dog. A dog is also considered dangerous if its bark frightens people.17 Although some are lenient regarding this injunction, a G‑d fearing person should be not be.
    If one must own a dangerous dog, he must keep it chained up, in a manner which renders the dog incapable of harming people.
  • One may not own a dangerous dog. A dog is also considered dangerous if its bark frightens people...One may not slice bread, meat, or other items on the palm of one's hand,18 as one may accidentally cut one's hand.
  • Notifying a child that he will be punished in the future might agitate the child and cause him to harm himself. Rather, if it is necessary to punish a child, the punishment should be carried out immediately.19
  • Since smoking is now recognized as a health hazard, many contemporary halachic authorities are of the opinion that it is forbidden to smoke today. Others are of the opinion that although it is proper not to smoke, it is not strictly forbidden, especially if one is already addicted.20
    According to all opinions, however, one may demand that a person who is smoking should leave the room so as not to cause damage to others.

In addition to all of the above, there are other things – not mentioned here – which the Sages banned because they are spiritually harmful.