Abstract: This device facilitates field marking an arc of a circle having an obstructed center. It comprises a first clamp having a slot to engage a standard tape measure and a second clamp having another slot to engage a color-coded tape measure. A detachable swivel joint snap connects the first clamp to the second clamp, and a handle is connected to the first clamp. A method is provided to use the device, a standard tape measure, a color-coded tape measure, a rod, and a scribe to mark out such an arc. The method comprises identifying coordinates of an eccentric ellipse, whose foci are field accessible, that will substantially overlap the arc. The two tape measures are anchored to the two foci. The standard tape measure is stretched tight between the two foci while the color-coded tape measure provides a string line for marking out a closely fitting elliptical arc segment.

Abstract: A replacement drain cover apparatus for a swimming pool drain to protect a swimmer from entrapment of the swimmer's body or hair and having a drain sump adapter ring for securing means into a pool drain sump and an installation plate for releasably securing onto the adapter ring and for positioning the adapter ring in a pool drain sump for securing the adapter ring in the correct position in the pool drain sump for a drain cover. An anti-entrapment drain cover having a size substantially greater than the pool drain sump is secured to the adapter ring to cover the drain sump and has sufficient cross sectional area so that the velocity of flow under and though the drain cover at any point on the drain cover even if partially blocked by a swimmer is at a rate to protect a swimmer from entrapment of the swimmer's body and hair.

Abstract: This device facilitates field marking an arc of a circle having an obstructed center. It comprises a first clamp having a slot to engage a standard tape measure and a second clamp having another slot to engage a color-coded tape measure. A detachable swivel joint snap connects the first clamp to the second clamp, and a handle is connected to the first clamp.

Abstract: A replacement drain cover apparatus for a swimming pool drain to protect a swimmer from entrapment of the swimmer's body or hair and having a drain sump adapter ring for securing means into a pool drain sump and an installation plate for releasably securing onto the adapter ring and for positioning the adapter ring in a pool drain sump for securing the adapter ring in the correct position in the pool drain sump for a drain cover. An antientrapment drain cover having a size substantially greater than the pool drain sump is secured to the adapter ring to cover the drain sump and has sufficient cross sectional area so that the velocity of flow under and though the drain cover at any point on the drain cover even if partially blocked by a swimmer is at a rate to protect a swimmer from entrapment of the swimmer's body and hair.

Abstract: The present invention entails a prefabricated safety device and method for installing the device in any swimming pool and that is capable of eliminating dangerous vacuum pressure created in the main drain line of a pool when an object or person becomes trapped against the drain or other suction line inlet of a swimming pool recirculating pump system. The vacuum elimination safety device is prefabricated and is a complete kit (unit) that can easily be installed directly onto the main drain suction line of any swimming pool recirculating pump system.

Abstract: A main drain safety grate apparatus utilizes an elongate drain, frame and grate that distribute the suction flow of water over a large surface to avoid full blockage of the grate, and also utilizes a bendable or deformable, upwardly releasable grate that has a section slotted to permit water to drain therethrough. The grate is ordinarily restrained from upward movement by a slot in each end of the frame into which the ends of the grate fit, and from downward movement by two shelves on which the grate may be supported. The grate may be released from the frame by an upward force applied at the section provided for drainage, which bends, or bows, the grate in an arcuate shape, and acts to shorten the length of the grate relative to the slots into which it is fitted.